1. Home
  2. Vulnerabilities
  3. CVE-2026-8391
7.5
HIGH CVSS 3.1
CVE-2026-8391
Other issue in the JavaScript Engine component
Overview
Description

Other issue in the JavaScript Engine component. This vulnerability was fixed in Firefox 150.0.3, Firefox ESR 115.36, Firefox ESR 140.11, and Thunderbird 140.11.

Details
INFO

Published Date :

May 12, 2026, 2:17 p.m.

Last Modified :

July 15, 2026, 1:17 a.m.

Remotely Exploit :

Yes !

Source :

[email protected]
Impact
Affected Products

The following products are affected by CVE-2026-8391 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Mozilla firefox
2 Mozilla thunderbird
: Total Affected Vendor : 1 | Products : 2
Scoring
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 MEDIUM 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 HIGH 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
Solution
Update the product to the latest version to fix security issues.
  • Update the product to the latest version.
References
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-8391.

URL Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=2038575 Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-45/ Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-47/
https://www.mozilla.org/security/advisories/mfsa2026-48/
https://www.mozilla.org/security/advisories/mfsa2026-51/
https://access.redhat.com/errata/RHSA-2026:21378
https://access.redhat.com/errata/RHSA-2026:21380
https://access.redhat.com/errata/RHSA-2026:21381
https://access.redhat.com/errata/RHSA-2026:21382
https://access.redhat.com/errata/RHSA-2026:22325
https://access.redhat.com/errata/RHSA-2026:22643
https://access.redhat.com/errata/RHSA-2026:26174
https://access.redhat.com/errata/RHSA-2026:26268
https://access.redhat.com/errata/RHSA-2026:26269
https://access.redhat.com/errata/RHSA-2026:26270
https://access.redhat.com/errata/RHSA-2026:26491
https://access.redhat.com/errata/RHSA-2026:26492
https://access.redhat.com/errata/RHSA-2026:26493
https://access.redhat.com/errata/RHSA-2026:26521
https://access.redhat.com/errata/RHSA-2026:26536
https://access.redhat.com/errata/RHSA-2026:26539
https://access.redhat.com/errata/RHSA-2026:26551
https://access.redhat.com/errata/RHSA-2026:26606
https://access.redhat.com/errata/RHSA-2026:26629
https://access.redhat.com/errata/RHSA-2026:26630
https://access.redhat.com/errata/RHSA-2026:27715
https://access.redhat.com/security/cve/CVE-2026-8391
https://bugzilla.redhat.com/show_bug.cgi?id=2476475
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-8391.json
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-8391 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-8391 weaknesses.

CAPEC-3: Using Leading 'Ghost' Character Sequences to Bypass Input Filters Using Leading 'Ghost' Character Sequences to Bypass Input Filters CAPEC-7: Blind SQL Injection Blind SQL Injection CAPEC-8: Buffer Overflow in an API Call Buffer Overflow in an API Call CAPEC-9: Buffer Overflow in Local Command-Line Utilities Buffer Overflow in Local Command-Line Utilities CAPEC-10: Buffer Overflow via Environment Variables Buffer Overflow via Environment Variables CAPEC-13: Subverting Environment Variable Values Subverting Environment Variable Values CAPEC-14: Client-side Injection-induced Buffer Overflow Client-side Injection-induced Buffer Overflow CAPEC-22: Exploiting Trust in Client Exploiting Trust in Client CAPEC-23: File Content Injection File Content Injection CAPEC-24: Filter Failure through Buffer Overflow Filter Failure through Buffer Overflow CAPEC-28: Fuzzing Fuzzing CAPEC-31: Accessing/Intercepting/Modifying HTTP Cookies Accessing/Intercepting/Modifying HTTP Cookies CAPEC-42: MIME Conversion MIME Conversion CAPEC-43: Exploiting Multiple Input Interpretation Layers Exploiting Multiple Input Interpretation Layers CAPEC-45: Buffer Overflow via Symbolic Links Buffer Overflow via Symbolic Links CAPEC-46: Overflow Variables and Tags Overflow Variables and Tags CAPEC-47: Buffer Overflow via Parameter Expansion Buffer Overflow via Parameter Expansion CAPEC-52: Embedding NULL Bytes Embedding NULL Bytes CAPEC-53: Postfix, Null Terminate, and Backslash Postfix, Null Terminate, and Backslash CAPEC-63: Cross-Site Scripting (XSS) Cross-Site Scripting (XSS) CAPEC-64: Using Slashes and URL Encoding Combined to Bypass Validation Logic Using Slashes and URL Encoding Combined to Bypass Validation Logic CAPEC-67: String Format Overflow in syslog() String Format Overflow in syslog() CAPEC-71: Using Unicode Encoding to Bypass Validation Logic Using Unicode Encoding to Bypass Validation Logic CAPEC-72: URL Encoding URL Encoding CAPEC-73: User-Controlled Filename User-Controlled Filename CAPEC-78: Using Escaped Slashes in Alternate Encoding Using Escaped Slashes in Alternate Encoding CAPEC-79: Using Slashes in Alternate Encoding Using Slashes in Alternate Encoding CAPEC-80: Using UTF-8 Encoding to Bypass Validation Logic Using UTF-8 Encoding to Bypass Validation Logic CAPEC-81: Web Server Logs Tampering Web Server Logs Tampering CAPEC-83: XPath Injection XPath Injection CAPEC-85: AJAX Footprinting AJAX Footprinting CAPEC-88: OS Command Injection OS Command Injection CAPEC-101: Server Side Include (SSI) Injection Server Side Include (SSI) Injection CAPEC-104: Cross Zone Scripting Cross Zone Scripting CAPEC-108: Command Line Execution through SQL Injection Command Line Execution through SQL Injection CAPEC-109: Object Relational Mapping Injection Object Relational Mapping Injection CAPEC-110: SQL Injection through SOAP Parameter Tampering SQL Injection through SOAP Parameter Tampering CAPEC-120: Double Encoding Double Encoding CAPEC-135: Format String Injection Format String Injection CAPEC-136: LDAP Injection LDAP Injection CAPEC-153: Input Data Manipulation Input Data Manipulation CAPEC-182: Flash Injection Flash Injection CAPEC-209: XSS Using MIME Type Mismatch XSS Using MIME Type Mismatch CAPEC-230: Serialized Data with Nested Payloads Serialized Data with Nested Payloads CAPEC-231: Oversized Serialized Data Payloads Oversized Serialized Data Payloads CAPEC-250: XML Injection XML Injection CAPEC-261: Fuzzing for garnering other adjacent user/sensitive data Fuzzing for garnering other adjacent user/sensitive data CAPEC-267: Leverage Alternate Encoding Leverage Alternate Encoding CAPEC-473: Signature Spoof Signature Spoof CAPEC-588: DOM-Based XSS DOM-Based XSS CAPEC-664: Server Side Request Forgery Server Side Request Forgery CAPEC-63: Cross-Site Scripting (XSS) Cross-Site Scripting (XSS) CAPEC-85: AJAX Footprinting AJAX Footprinting CAPEC-209: XSS Using MIME Type Mismatch XSS Using MIME Type Mismatch CAPEC-588: DOM-Based XSS DOM-Based XSS CAPEC-591: Reflected XSS Reflected XSS CAPEC-592: Stored XSS Stored XSS CAPEC-8: Buffer Overflow in an API Call Buffer Overflow in an API Call CAPEC-9: Buffer Overflow in Local Command-Line Utilities Buffer Overflow in Local Command-Line Utilities CAPEC-10: Buffer Overflow via Environment Variables Buffer Overflow via Environment Variables CAPEC-14: Client-side Injection-induced Buffer Overflow Client-side Injection-induced Buffer Overflow CAPEC-24: Filter Failure through Buffer Overflow Filter Failure through Buffer Overflow CAPEC-42: MIME Conversion MIME Conversion CAPEC-44: Overflow Binary Resource File Overflow Binary Resource File CAPEC-45: Buffer Overflow via Symbolic Links Buffer Overflow via Symbolic Links CAPEC-46: Overflow Variables and Tags Overflow Variables and Tags CAPEC-47: Buffer Overflow via Parameter Expansion Buffer Overflow via Parameter Expansion CAPEC-100: Overflow Buffers Overflow Buffers CAPEC-123: Buffer Manipulation Buffer Manipulation

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-8391 vulnerability anywhere in the article.

Results are limited to the first 20 news articles due to potential performance issues.

The following table lists the changes that have been made to the CVE-2026-8391 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

    Jul. 15, 2026

    Action Type Old Value New Value
    Changed Affected [{'cpes': ['cpe:/o:redhat:rhel_els:7'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux Server (v. 7 ELS)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux_eus:10.0'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux AppStream EUS (v. 10.0)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux:10.2'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux AppStream (v. 10)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:enterprise_linux:8::appstream'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux AppStream (v. 8)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_aus:8.4::appstream'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux AppStream AUS (v.8.4)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_eus_long_life:8.4::appstream'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_aus:8.6::appstream'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux AppStream AUS (v.8.6)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_eus_long_life:8.6::appstream'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_e4s:8.8::appstream'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux AppStream E4S (v.8.8)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_tus:8.8::appstream'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux AppStream TUS (v.8.8)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_e4s:9.2::appstream'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux AppStream E4S (v.9.2)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_e4s:9.4::appstream'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux AppStream E4S (v.9.4)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_eus:9.6::appstream'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux AppStream EUS (v.9.6)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:enterprise_linux:9::appstream'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux AppStream (v. 9)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux:10'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 10', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux:6'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 6', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux:7'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 7', 'defaultStatus': 'affected'}] [{'cpes': ['cpe:/o:redhat:enterprise_linux:10.2'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 10', 'versions': [{'status': 'unaffected', 'version': '0:140.11.0-1.el10_2', 'lessThan': '*', 'versionType': 'rpm'}], 'packageName': 'firefox', 'collectionURL': 'https://catalog.redhat.com/software/containers/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux:10.2'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 10', 'versions': [{'status': 'unaffected', 'version': '0:140.11.0-1.el10_2', 'lessThan': '*', 'versionType': 'rpm'}], 'packageName': 'thunderbird', 'collectionURL': 'https://catalog.redhat.com/software/containers/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux_eus:10.0'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 10.0 Extended Update Support', 'versions': [{'status': 'unaffected', 'version': '0:140.11.0-1.el10_0', 'lessThan': '*', 'versionType': 'rpm'}], 'packageName': 'thunderbird', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux_eus:10.0'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 10.0 Extended Update Support', 'versions': [{'status': 'unaffected', 'version': '0:140.11.0-1.el10_0', 'lessThan': '*', 'versionType': 'rpm'}], 'packageName': 'firefox', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/o:redhat:rhel_els:7'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 7 Extended Lifecycle Support', 'versions': [{'status': 'unaffected', 'version': '0:140.11.0-1.el7_9', 'lessThan': '*', 'versionType': 'rpm'}], 'packageName': 'firefox', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:enterprise_linux:8'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 8', 'versions': [{'status': 'unaffected', 'version': '0:140.11.0-1.el8_10', 'lessThan': '*', 'versionType': 'rpm'}], 'packageName': 'firefox', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:enterprise_linux:8'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 8', 'versions': [{'status': 'unaffected', 'version': '0:140.11.0-1.el8_10', 'lessThan': '*', 'versionType': 'rpm'}], 'packageName': 'thunderbird', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_aus:8.4'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support', 'versions': [{'status': 'unaffected', 'version': '0:140.11.0-1.el8_4', 'lessThan': '*', 'versionType': 'rpm'}], 'packageName': 'thunderbird', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_aus:8.4'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support', 'versions': [{'status': 'unaffected', 'version': '0:140.11.0-1.el8_4', 'lessThan': '*', 'versionType': 'rpm'}], 'packageName': 'firefox', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_eus_long_life:8.4'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On', 'versions': [{'status': 'unaffected', 'version': '0:140.11.0-1.el8_4', 'lessThan': '*', 'versionType': 'rpm'}], 'packageName': 'thunderbird', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_eus_long_life:8.4'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On', 'versions': [{'status': 'unaffected', 'version': '0:140.11.0-1.el8_4', 'lessThan': '*', 'versionType': 'rpm'}], 'packageName': 'firefox', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_aus:8.6'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support', 'versions': [{'status': 'unaffected', 'version': '0:140.11.0-1.el8_6', 'lessThan': '*', 'versionType': 'rpm'}], 'packageName': 'thunderbird', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_aus:8.6'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support', 'versions': [{'status': 'unaffected', 'version': '0:140.11.0-1.el8_6', 'lessThan': '*', 'versionType': 'rpm'}], 'packageName': 'firefox', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_eus_long_life:8.6'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On', 'versions': [{'status': 'unaffected', 'version': '0:140.11.0-1.el8_6', 'lessThan': '*', 'versionType': 'rpm'}], 'packageName': 'thunderbird', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_eus_long_life:8.6'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On', 'versions': [{'status': 'unaffected', 'version': '0:140.11.0-1.el8_6', 'lessThan': '*', 'versionType': 'rpm'}], 'packageName': 'firefox', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_tus:8.8'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 8.8 Telecommunications Update Service', 'versions': [{'status': 'unaffected', 'version': '0:140.11.0-1.el8_8', 'lessThan': '*', 'versionType': 'rpm'}], 'packageName': 'thunderbird', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_tus:8.8'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 8.8 Telecommunications Update Service', 'versions': [{'status': 'unaffected', 'version': '0:140.11.0-1.el8_8', 'lessThan': '*', 'versionType': 'rpm'}], 'packageName': 'firefox', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_e4s:8.8'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions', 'versions': [{'status': 'unaffected', 'version': '0:140.11.0-1.el8_8', 'lessThan': '*', 'versionType': 'rpm'}], 'packageName': 'thunderbird', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_e4s:8.8'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions', 'versions': [{'status': 'unaffected', 'version': '0:140.11.0-1.el8_8', 'lessThan': '*', 'versionType': 'rpm'}], 'packageName': 'firefox', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:enterprise_linux:9'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 9', 'versions': [{'status': 'unaffected', 'version': '0:140.11.0-1.el9_8', 'lessThan': '*', 'versionType': 'rpm'}], 'packageName': 'firefox', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:enterprise_linux:9'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 9', 'versions': [{'status': 'unaffected', 'version': '0:140.11.0-1.el9_8', 'lessThan': '*', 'versionType': 'rpm'}], 'packageName': 'thunderbird', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_e4s:9.2'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions', 'versions': [{'status': 'unaffected', 'version': '0:140.11.0-1.el9_2', 'lessThan': '*', 'versionType': 'rpm'}], 'packageName': 'thunderbird', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_e4s:9.2'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions', 'versions': [{'status': 'unaffected', 'version': '0:140.11.0-1.el9_2', 'lessThan': '*', 'versionType': 'rpm'}], 'packageName': 'firefox', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_e4s:9.4'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions', 'versions': [{'status': 'unaffected', 'version': '0:140.11.0-1.el9_4', 'lessThan': '*', 'versionType': 'rpm'}], 'packageName': 'thunderbird', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_e4s:9.4'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions', 'versions': [{'status': 'unaffected', 'version': '0:140.11.0-1.el9_4', 'lessThan': '*', 'versionType': 'rpm'}], 'packageName': 'firefox', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_eus:9.6'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 9.6 Extended Update Support', 'versions': [{'status': 'unaffected', 'version': '0:140.11.0-1.el9_6', 'lessThan': '*', 'versionType': 'rpm'}], 'packageName': 'firefox', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_eus:9.6'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 9.6 Extended Update Support', 'versions': [{'status': 'unaffected', 'version': '0:140.11.0-1.el9_6', 'lessThan': '*', 'versionType': 'rpm'}], 'packageName': 'thunderbird', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux:10'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 10', 'packageName': 'rhel10/firefox-flatpak', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux:10'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 10', 'packageName': 'rhel10/thunderbird-flatpak', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux:6'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 6', 'packageName': 'firefox', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'unknown'}, {'cpes': ['cpe:/o:redhat:enterprise_linux:6'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 6', 'packageName': 'thunderbird', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'unknown'}, {'cpes': ['cpe:/o:redhat:enterprise_linux:7'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 7', 'packageName': 'thunderbird', 'collectionURL': 'https://access.redhat.com/downloads/content/package-browser/', 'defaultStatus': 'unknown'}]
  • CVE Modified by 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

    Jun. 30, 2026

    Action Type Old Value New Value
    Added Affected [{'cpes': ['cpe:/o:redhat:rhel_els:7'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux Server (v. 7 ELS)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux_eus:10.0'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux AppStream EUS (v. 10.0)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux:10.2'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux AppStream (v. 10)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:enterprise_linux:8::appstream'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux AppStream (v. 8)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_aus:8.4::appstream'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux AppStream AUS (v.8.4)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_eus_long_life:8.4::appstream'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_aus:8.6::appstream'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux AppStream AUS (v.8.6)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_eus_long_life:8.6::appstream'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_e4s:8.8::appstream'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux AppStream E4S (v.8.8)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_tus:8.8::appstream'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux AppStream TUS (v.8.8)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_e4s:9.2::appstream'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux AppStream E4S (v.9.2)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_e4s:9.4::appstream'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux AppStream E4S (v.9.4)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:rhel_eus:9.6::appstream'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux AppStream EUS (v.9.6)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:enterprise_linux:9::appstream'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux AppStream (v. 9)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux:10'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 10', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux:6'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 6', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux:7'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 7', 'defaultStatus': 'affected'}]
    Added CVSS V3.1 AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
    Added CWE CWE-475
    Added Reference https://access.redhat.com/errata/RHSA-2026:21378
    Added Reference https://access.redhat.com/errata/RHSA-2026:21380
    Added Reference https://access.redhat.com/errata/RHSA-2026:21381
    Added Reference https://access.redhat.com/errata/RHSA-2026:21382
    Added Reference https://access.redhat.com/errata/RHSA-2026:22325
    Added Reference https://access.redhat.com/errata/RHSA-2026:22643
    Added Reference https://access.redhat.com/errata/RHSA-2026:26174
    Added Reference https://access.redhat.com/errata/RHSA-2026:26268
    Added Reference https://access.redhat.com/errata/RHSA-2026:26269
    Added Reference https://access.redhat.com/errata/RHSA-2026:26270
    Added Reference https://access.redhat.com/errata/RHSA-2026:26491
    Added Reference https://access.redhat.com/errata/RHSA-2026:26492
    Added Reference https://access.redhat.com/errata/RHSA-2026:26493
    Added Reference https://access.redhat.com/errata/RHSA-2026:26521
    Added Reference https://access.redhat.com/errata/RHSA-2026:26536
    Added Reference https://access.redhat.com/errata/RHSA-2026:26539
    Added Reference https://access.redhat.com/errata/RHSA-2026:26551
    Added Reference https://access.redhat.com/errata/RHSA-2026:26606
    Added Reference https://access.redhat.com/errata/RHSA-2026:26629
    Added Reference https://access.redhat.com/errata/RHSA-2026:26630
    Added Reference https://access.redhat.com/errata/RHSA-2026:27715
    Added Reference https://access.redhat.com/security/cve/CVE-2026-8391
    Added Reference https://bugzilla.redhat.com/show_bug.cgi?id=2476475
    Added Reference https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-8391.json
  • CVE Modified by [email protected]

    Jun. 17, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'Mozilla', 'product': 'Firefox', 'versions': [{'status': 'unaffected', 'version': '115.36', 'versionType': 'rpm', 'lessThanOrEqual': '115.*'}, {'status': 'unaffected', 'version': '140.11', 'versionType': 'rpm', 'lessThanOrEqual': '140.*'}, {'status': 'unaffected', 'version': '150.0.3', 'versionType': 'rpm', 'lessThanOrEqual': '*'}]}, {'vendor': 'Mozilla', 'product': 'Thunderbird', 'versions': [{'status': 'unaffected', 'version': '140.11', 'versionType': 'rpm', 'lessThanOrEqual': '*'}]}]
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Jun. 17, 2026

    Action Type Old Value New Value
    Added SSVC {'id': 'CVE-2026-8391', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-05-13T15:47:19.047188Z'}
  • CVE Modified by [email protected]

    May. 19, 2026

    Action Type Old Value New Value
    Changed Description Other issue in the JavaScript Engine component. This vulnerability was fixed in Firefox 150.0.3, Firefox ESR 115.36, and Firefox ESR 140.11. Other issue in the JavaScript Engine component. This vulnerability was fixed in Firefox 150.0.3, Firefox ESR 115.36, Firefox ESR 140.11, and Thunderbird 140.11.
    Added Reference https://www.mozilla.org/security/advisories/mfsa2026-51/
  • CVE Modified by [email protected]

    May. 19, 2026

    Action Type Old Value New Value
    Changed Description Other issue in the JavaScript Engine component. This vulnerability was fixed in Firefox 150.0.3. Other issue in the JavaScript Engine component. This vulnerability was fixed in Firefox 150.0.3, Firefox ESR 115.36, and Firefox ESR 140.11.
    Added Reference https://www.mozilla.org/security/advisories/mfsa2026-47/
    Added Reference https://www.mozilla.org/security/advisories/mfsa2026-48/
  • Initial Analysis by [email protected]

    May. 13, 2026

    Action Type Old Value New Value
    Added CPE Configuration OR *cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:* versions up to (excluding) 150.0.3
    Added Reference Type Mozilla Corporation: https://bugzilla.mozilla.org/show_bug.cgi?id=2038575 Types: Permissions Required
    Added Reference Type Mozilla Corporation: https://www.mozilla.org/security/advisories/mfsa2026-45/ Types: Vendor Advisory
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    May. 13, 2026

    Action Type Old Value New Value
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
    Added CWE CWE-119
    Added CWE CWE-79
    Added CWE CWE-20
  • New CVE Received by [email protected]

    May. 12, 2026

    Action Type Old Value New Value
    Added Description Other issue in the JavaScript Engine component. This vulnerability was fixed in Firefox 150.0.3.
    Added Reference https://bugzilla.mozilla.org/show_bug.cgi?id=2038575
    Added Reference https://www.mozilla.org/security/advisories/mfsa2026-45/
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CVSS
Vulnerability Scoring Details
Base CVSS Score: 7.5
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact