6.3
MEDIUM CVSS 4.0
CVE-2026-48142
NGINX ngx_http_charset_module vulnerability
Description

NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_charset_module module. When content is served or proxied through a location block with both source_charset utf-8; and a charset directive (for example, charset koi8-r;) configured, remote, unauthenticated attackers can send requests (in conjunction with conditions beyond their control) to cause a heap buffer over-read in the NGINX worker process, leading to limited disclosure of memory or a restart. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

INFO

Published Date :

June 17, 2026, 3:16 p.m.

Last Modified :

June 22, 2026, 4:50 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-48142 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 F5 nginx_instance_manager
2 F5 nginx_ingress_controller
3 F5 nginx_plus
4 F5 nginx_open_source
5 F5 nginx_gateway_fabric
6 F5 dos
7 F5 waf
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 9dacffd4-cb11-413f-8451-fbbfd4ddc0ab
CVSS 3.1 MEDIUM [email protected]
CVSS 4.0 MEDIUM 9dacffd4-cb11-413f-8451-fbbfd4ddc0ab
CVSS 4.0 MEDIUM [email protected]
Solution
Update NGINX to a patched version to fix a heap buffer over-read vulnerability.
  • Update NGINX to a version that includes the fix.
  • Remove duplicate charset directives.
  • Review module configurations for proper charset usage.
Public PoC/Exploit Available at Github

CVE-2026-48142 has a 3 public PoC/Exploit available at Github. Go to the Public Exploits tab to see the list.

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-2026-48142.

URL Resource
https://my.f5.com/manage/s/article/K000161585 Vendor Advisory
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-48142 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-2026-48142 weaknesses.

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).

Web Application Firewall for nginx

CMake C Shell C++ HTML PHP Perl Python

Updated: 1 week, 5 days ago
2 stars 0 fork 0 watcher
Born at : June 13, 2026, 6:06 p.m. This repo has been linked 3 different CVEs too.

WNMP One‑Click Stack | WebDAV · Nginx · PHP · MariaDB · Kernel Tuning

Shell HTML

Updated: 2 weeks, 4 days ago
25 stars 4 fork 4 watcher
Born at : Dec. 7, 2025, 11:39 p.m. This repo has been linked 10 different CVEs too.

None

Updated: 2 weeks, 5 days ago
0 stars 0 fork 0 watcher
Born at : Nov. 3, 2023, 7:48 a.m. This repo has been linked 3 different CVEs too.

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

The following list is the news that have been mention CVE-2026-48142 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-48142 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.

  • Initial Analysis by [email protected]

    Jun. 22, 2026

    Action Type Old Value New Value
    Added CPE Configuration OR *cpe:2.3:a:f5:nginx_ingress_controller:*:*:*:*:*:*:*:* versions from (including) 4.0.0 up to (including) 4.0.1 *cpe:2.3:a:f5:nginx_gateway_fabric:*:*:*:*:*:*:*:* versions from (including) 1.3.0 up to (including) 1.6.2 *cpe:2.3:a:f5:nginx_ingress_controller:*:*:*:*:*:*:*:* versions from (including) 3.5.0 up to (including) 3.7.2 *cpe:2.3:a:f5:dos:*:*:*:*:*:nginx:*:* versions from (including) 4.3.0 up to (including) 4.7.0 *cpe:2.3:a:f5:dos:4.9.0:*:*:*:*:nginx:*:* *cpe:2.3:a:f5:nginx_gateway_fabric:*:*:*:*:*:*:*:* versions from (including) 2.0.0 up to (including) 2.6.3 *cpe:2.3:a:f5:nginx_ingress_controller:*:*:*:*:*:*:*:* versions from (including) 5.0.0 up to (including) 5.5.0 *cpe:2.3:a:f5:nginx_instance_manager:*:*:*:*:*:*:*:* versions from (including) 2.17.0 up to (including) 2.22.0 *cpe:2.3:a:f5:nginx_open_source:*:*:*:*:*:*:*:* versions from (including) 1.0.0 up to (including) 1.30.2 *cpe:2.3:a:f5:nginx_open_source:*:*:*:*:*:*:*:* versions from (including) 1.31.0 up to (including) 1.31.1 *cpe:2.3:a:f5:nginx_plus:*:*:*:*:*:*:*:* versions from (including) 37.0.0 up to (including) 37.0.1 *cpe:2.3:a:f5:nginx_plus:*:*:*:*:*:*:*:* versions from (including) r33 up to (including) r36 *cpe:2.3:a:f5:waf:*:*:*:*:*:nginx:*:* versions from (including) 4.10.0 up to (including) 4.16.0 *cpe:2.3:a:f5:waf:*:*:*:*:*:nginx:*:* versions from (including) 5.2.0 up to (including) 5.8.0 *cpe:2.3:a:f5:waf:*:*:*:*:*:nginx:*:* versions from (including) 5.9.0 up to (including) 5.13.1
    Added Reference Type F5 Networks: https://my.f5.com/manage/s/article/K000161585 Types: Vendor Advisory
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Jun. 17, 2026

    Action Type Old Value New Value
    Added SSVC {'id': 'CVE-2026-48142', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-06-17T15:42:46.410409Z'}
  • New CVE Received by [email protected]

    Jun. 17, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'F5', 'modules': ['ngx_http_charset_module'], 'product': 'NGINX Open Source', 'versions': [{'status': 'affected', 'version': '1.13.10', 'lessThan': '1.31.2', 'versionType': 'custom'}, {'status': 'affected', 'version': '1.30.0', 'lessThan': '1.30.3', 'versionType': 'custom'}], 'defaultStatus': 'unknown'}, {'vendor': 'F5', 'modules': ['ngx_http_charset_module'], 'product': 'NGINX Plus', 'versions': [{'status': 'affected', 'version': '37.0', 'lessThan': '37.0.2.1', 'versionType': 'custom'}, {'status': 'affected', 'version': 'R36', 'lessThan': 'R36 P6', 'versionType': 'custom'}], 'defaultStatus': 'unaffected'}]
    Added Description NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_charset_module module. When content is served or proxied through a location block with both source_charset utf-8; and a charset directive (for example, charset koi8-r;) configured, remote, unauthenticated attackers can send requests (in conjunction with conditions beyond their control) to cause a heap buffer over-read in the NGINX worker process, leading to limited disclosure of memory or a restart. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
    Added CVSS V4.0 AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
    Added CWE CWE-125
    Added Reference https://my.f5.com/manage/s/article/K000161585
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.