10.0
CRITICAL
CVSS 4.0
CVE-2026-5588
PKIX draft CompositeVerifier accepts empty signature sequence as valid.
Overview
Description
Use of a Broken or Risky Cryptographic Algorithm vulnerability in Legion of the Bouncy Castle Inc. BC-JAVA bcpkix on all (pkix modules), Legion of the Bouncy Castle Inc. BCPKIX-FIPS bcpkix on All (pkix modules), Legion of the Bouncy Castle Inc. BCPIX-LTS bcpkix on All (pkix modules). This vulnerability is associated with program files JcaContentVerifierProviderBuilder.Java, JcaContentVerfierProviderBuilder.Java. This issue affects BC-JAVA: from 1.67 before 1.80.2, from 1.81 before 1.81.1, from 1.82 before 1.84; BCPKIX-FIPS: from 2.0.6 before 2.0.11, from 2.1.7 before 2.1.11; BCPIX-LTS: from 2.73.7 before 2.73.11.
Details
INFO
Published Date :
April 15, 2026, 10:16 a.m.
Last Modified :
June 30, 2026, 3:21 a.m.
Remotely Exploit :
Yes !
Source :
91579145-5d7b-4cc5-b925-a0262ff19630
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 | HIGH | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | ||||
| CVSS 4.0 | CRITICAL | 91579145-5d7b-4cc5-b925-a0262ff19630 | ||||
| CVSS 4.0 | CRITICAL | 91579145-5d7b-4cc5-b925-a0262ff19630 | ||||
| CVSS 4.0 | MEDIUM | 91579145-5d7b-4cc5-b925-a0262ff19630 | ||||
| CVSS 4.0 | MEDIUM | 91579145-5d7b-4cc5-b925-a0262ff19630 |
Solution
Update the BC-JAVA library to a version that addresses the cryptographic validation issue.
- Update BC-JAVA library to version 1.84 or later.
- Verify cryptographic validation logic.
- Apply vendor-provided patches if available.
Public PoC/Exploit Available at Github
CVE-2026-5588 has a 2 public
PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
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-2026-5588.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-5588 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-2026-5588
weaknesses.
CAPEC-20: Encryption Brute Forcing Encryption Brute Forcing
CAPEC-97: Cryptanalysis Cryptanalysis
CAPEC-459: Creating a Rogue Certification Authority Certificate Creating a Rogue Certification Authority Certificate
CAPEC-473: Signature Spoof Signature Spoof
CAPEC-475: Signature Spoofing by Improper Validation Signature Spoofing by Improper Validation
CAPEC-608: Cryptanalysis of Cellular Encryption Cryptanalysis of Cellular Encryption
CAPEC-614: Rooting SIM Cards Rooting SIM Cards
CAPEC-463: Padding Oracle Crypto Attack Padding Oracle Crypto Attack
CAPEC-475: Signature Spoofing by Improper Validation Signature Spoofing by Improper Validation
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).
Tracking CVEs discovered by AI systems — Anthropic, OpenAI, Google Big Sleep, Microsoft MDASH, DepthFirst
Updated: 1 week, 1 day ago
1 stars
0 fork
0 watcher
Born at : May 26, 2026, 1:31 a.m.
This repo has been linked 208 different CVEs too.
Tracking Vulnerabilities That Appear to be Credited to the Anthropic Research Team
Updated: 1 month ago
21 stars
3 fork
3 watcher
Born at : April 17, 2026, 4:15 p.m.
This repo has been linked 83 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-2026-5588 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-5588 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
Jun. 30, 2026
Action Type Old Value New Value Added Affected [{'cpes': ['cpe:/a:redhat:jboss_enterprise_application_platform:8.1::el8'], 'vendor': 'Red Hat', 'product': 'Red Hat JBoss EAP 8.1 for RHEL 8', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:jboss_enterprise_application_platform:8.1::el9'], 'vendor': 'Red Hat', 'product': 'Red Hat JBoss EAP 8.1 for RHEL 9', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:amq_broker:7.12'], 'vendor': 'Red Hat', 'product': 'Red Hat AMQ Broker 7.12.7', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:amq_broker:7.13'], 'vendor': 'Red Hat', 'product': 'Red Hat AMQ Broker 7.13.5', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:apache_camel_quarkus:3.27'], 'vendor': 'Red Hat', 'product': 'Red Hat Build of Apache Camel 4.14 for Quarkus 3.27', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:jboss_enterprise_application_platform:8.1::el9'], 'vendor': 'Red Hat', 'product': 'Red Hat JBoss Enterprise Application Platform 8.1', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:openshift_devspaces:3.28::el9'], 'vendor': 'Red Hat', 'product': 'Red Hat OpenShift Dev Spaces 3.28', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:apache_camel_spring_boot:4.18'], 'vendor': 'Red Hat', 'product': 'Red Hat build of Apache Camel 4.18.1 for Spring Boot 3.5.14', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:quarkus:3.20::el8'], 'vendor': 'Red Hat', 'product': 'Red Hat build of Quarkus 3.20.6.SP1', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:quarkus:3.27::el8'], 'vendor': 'Red Hat', 'product': 'Red Hat build of Quarkus 3.27.3.SP1', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:ocp_tools'], 'vendor': 'Red Hat', 'product': 'OpenShift Developer Tools and Services', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:camel_quarkus:3'], 'vendor': 'Red Hat', 'product': 'Red Hat build of Apache Camel 4 for Quarkus 3', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:apicurio_registry:3'], 'vendor': 'Red Hat', 'product': 'Red Hat build of Apicurio Registry 3', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:debezium:3'], 'vendor': 'Red Hat', 'product': 'Red Hat build of Debezium 3', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux:8'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 8', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:jboss_fuse:7'], 'vendor': 'Red Hat', 'product': 'Red Hat Fuse 7', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:jboss_enterprise_application_platform:7'], 'vendor': 'Red Hat', 'product': 'Red Hat JBoss Enterprise Application Platform 7', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:openshift_ai'], 'vendor': 'Red Hat', 'product': 'Red Hat OpenShift AI (RHOAI)', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:jboss_enterprise_bpms_platform:7'], 'vendor': 'Red Hat', 'product': 'Red Hat Process Automation 7', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:red_hat_single_sign_on:7'], 'vendor': 'Red Hat', 'product': 'Red Hat Single Sign-On 7', 'defaultStatus': 'affected'}, {'cpes': ['cpe:/a:redhat:cryostat:4'], 'vendor': 'Red Hat', 'product': 'Cryostat 4', 'defaultStatus': 'unaffected'}, {'cpes': ['cpe:/a:redhat:amq_broker:7'], 'vendor': 'Red Hat', 'product': 'Red Hat AMQ Broker 7', 'defaultStatus': 'unaffected'}, {'cpes': ['cpe:/a:redhat:jboss_data_grid:8'], 'vendor': 'Red Hat', 'product': 'Red Hat Data Grid 8', 'defaultStatus': 'unaffected'}, {'cpes': ['cpe:/o:redhat:enterprise_linux:9'], 'vendor': 'Red Hat', 'product': 'Red Hat Enterprise Linux 9', 'defaultStatus': 'unaffected'}, {'cpes': ['cpe:/a:redhat:jbosseapxp'], 'vendor': 'Red Hat', 'product': 'Red Hat JBoss Enterprise Application Platform Expansion Pack', 'defaultStatus': 'unaffected'}, {'cpes': ['cpe:/a:redhat:satellite:6'], 'vendor': 'Red Hat', 'product': 'Red Hat Satellite 6', 'defaultStatus': 'unaffected'}, {'cpes': ['cpe:/a:redhat:amq_streams:2'], 'vendor': 'Red Hat', 'product': 'streams for Apache Kafka 2', 'defaultStatus': 'unaffected'}, {'cpes': ['cpe:/a:redhat:amq_streams:3'], 'vendor': 'Red Hat', 'product': 'streams for Apache Kafka 3', 'defaultStatus': 'unaffected'}] Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N Added CWE CWE-347 Added Reference https://access.redhat.com/errata/RHSA-2026:11720 Added Reference https://access.redhat.com/errata/RHSA-2026:11721 Added Reference https://access.redhat.com/errata/RHSA-2026:13631 Added Reference https://access.redhat.com/errata/RHSA-2026:14272 Added Reference https://access.redhat.com/errata/RHSA-2026:14276 Added Reference https://access.redhat.com/errata/RHSA-2026:17668 Added Reference https://access.redhat.com/errata/RHSA-2026:18054 Added Reference https://access.redhat.com/errata/RHSA-2026:18055 Added Reference https://access.redhat.com/errata/RHSA-2026:18059 Added Reference https://access.redhat.com/errata/RHSA-2026:21772 Added Reference https://access.redhat.com/security/cve/CVE-2026-5588 Added Reference https://bugzilla.redhat.com/show_bug.cgi?id=2458634 Added Reference https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-5588.json -
CVE Modified by 91579145-5d7b-4cc5-b925-a0262ff19630
Jun. 17, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://github.com/bcgit/bc-java', 'vendor': 'Legion of the Bouncy Castle Inc.', 'modules': ['pkix'], 'product': 'BC-JAVA', 'versions': [{'status': 'affected', 'version': '1.67', 'lessThan': '1.80.2', 'versionType': 'maven'}, {'status': 'affected', 'version': '1.81', 'lessThan': '1.81.1', 'versionType': 'maven'}, {'status': 'affected', 'version': '1.82', 'lessThan': '1.84', 'versionType': 'maven'}], 'platforms': ['all'], 'packageName': 'bcpkix', 'programFiles': ['JcaContentVerifierProviderBuilder.java'], 'collectionURL': 'https://www.bouncycastle.org/download/bouncy-castle-java/', 'defaultStatus': 'unaffected'}, {'repo': 'https://repo1.maven.org/maven2/org/bouncycastle/bcpkix-fips/', 'vendor': 'Legion of the Bouncy Castle Inc.', 'modules': ['pkix'], 'product': 'BCPKIX-FIPS', 'versions': [{'status': 'affected', 'version': '2.0.6', 'lessThan': '2.0.11', 'versionType': 'maven'}, {'status': 'affected', 'version': '2.1.7', 'lessThan': '2.1.11', 'versionType': 'maven'}], 'platforms': ['All'], 'packageName': 'bcpkix', 'programFiles': ['JcaContentVerifierProviderBuilder.java'], 'collectionURL': 'https://www.bouncycastle.org/download/bouncy-castle-java-fips/', 'defaultStatus': 'unaffected'}, {'repo': 'https://repo1.maven.org/maven2/org/bouncycastle/bcpkix-lts8on/', 'vendor': 'Legion of the Bouncy Castle Inc.', 'modules': ['pkix'], 'product': 'BCPIX-LTS', 'versions': [{'status': 'affected', 'version': '2.73.7', 'lessThan': '2.73.11', 'versionType': 'maven'}], 'platforms': ['All'], 'packageName': 'bcpkix', 'programFiles': ['JcaContentVerfierProviderBuilder.java'], 'collectionURL': 'https://www.bouncycastle.org/download/bouncy-castle-java-lts/', 'defaultStatus': 'unaffected'}] -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 17, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-5588', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-04-15T19:35:32.235455Z'} -
CVE Modified by 91579145-5d7b-4cc5-b925-a0262ff19630
May. 19, 2026
Action Type Old Value New Value Changed Description Use of a Broken or Risky Cryptographic Algorithm vulnerability in Legion of the Bouncy Castle Inc. BC-JAVA bcpkix on all (pkix modules), Legion of the Bouncy Castle Inc. BCPKIX-FIPS bcpkix on All (pkix modules), Legion of the Bouncy Castle Inc. BCPIX-LTS bcpkix on All (pkix modules). This vulnerability is associated with program files JcaContentVerifierProviderBuilder.Java, JcaContentVerfierProviderBuilder.Java. This issue affects BC-JAVA: from 1.67 before 1.84; BCPKIX-FIPS: from 2.0.6 before 2.0.11, from 2.1.7 before 2.1.11; BCPIX-LTS: from 2.73.7 before 2.73.11. Use of a Broken or Risky Cryptographic Algorithm vulnerability in Legion of the Bouncy Castle Inc. BC-JAVA bcpkix on all (pkix modules), Legion of the Bouncy Castle Inc. BCPKIX-FIPS bcpkix on All (pkix modules), Legion of the Bouncy Castle Inc. BCPIX-LTS bcpkix on All (pkix modules). This vulnerability is associated with program files JcaContentVerifierProviderBuilder.Java, JcaContentVerfierProviderBuilder.Java. This issue affects BC-JAVA: from 1.67 before 1.80.2, from 1.81 before 1.81.1, from 1.82 before 1.84; BCPKIX-FIPS: from 2.0.6 before 2.0.11, from 2.1.7 before 2.1.11; BCPIX-LTS: from 2.73.7 before 2.73.11. -
CVE Modified by 91579145-5d7b-4cc5-b925-a0262ff19630
May. 08, 2026
Action Type Old Value New Value Changed Description Use of a Broken or Risky Cryptographic Algorithm vulnerability in Legion of the Bouncy Castle Inc. BC-JAVA bcpkix on all (pkix modules), Legion of the Bouncy Castle Inc. BCPKIX-FIPS bcpkix on All (pkix modules). This vulnerability is associated with program files JcaContentVerifierProviderBuilder.Java. This issue affects BC-JAVA: from 1.67 before 1.84; BCPKIX-FIPS: from 2.0.6 before 2.0.11, from 2.1.7 before 2.1.11. Use of a Broken or Risky Cryptographic Algorithm vulnerability in Legion of the Bouncy Castle Inc. BC-JAVA bcpkix on all (pkix modules), Legion of the Bouncy Castle Inc. BCPKIX-FIPS bcpkix on All (pkix modules), Legion of the Bouncy Castle Inc. BCPIX-LTS bcpkix on All (pkix modules). This vulnerability is associated with program files JcaContentVerifierProviderBuilder.Java, JcaContentVerfierProviderBuilder.Java. This issue affects BC-JAVA: from 1.67 before 1.84; BCPKIX-FIPS: from 2.0.6 before 2.0.11, from 2.1.7 before 2.1.11; BCPIX-LTS: from 2.73.7 before 2.73.11. -
CVE Modified by 91579145-5d7b-4cc5-b925-a0262ff19630
Apr. 21, 2026
Action Type Old Value New Value Changed Description : Use of a Broken or Risky Cryptographic Algorithm vulnerability in Legion of the Bouncy Castle Inc. BC-JAVA bcpkix on all (pkix modules). PKIX draft CompositeVerifier accepts empty signature sequence as valid. This issue affects BC-JAVA: from 1.49 before 1.84. Use of a Broken or Risky Cryptographic Algorithm vulnerability in Legion of the Bouncy Castle Inc. BC-JAVA bcpkix on all (pkix modules), Legion of the Bouncy Castle Inc. BCPKIX-FIPS bcpkix on All (pkix modules). This vulnerability is associated with program files JcaContentVerifierProviderBuilder.Java. This issue affects BC-JAVA: from 1.67 before 1.84; BCPKIX-FIPS: from 2.0.6 before 2.0.11, from 2.1.7 before 2.1.11. Added CVSS V4.0 AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/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:Amber Removed CVSS V4.0 AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/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:Green Added Reference https://github.com/bcgit/bc-java/commit/656bae0dbd9b1521f840521ff786e78749fe3057 -
CVE Modified by 91579145-5d7b-4cc5-b925-a0262ff19630
Apr. 15, 2026
Action Type Old Value New Value Added CVSS V4.0 AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/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:Green Removed CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/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 -
New CVE Received by 91579145-5d7b-4cc5-b925-a0262ff19630
Apr. 15, 2026
Action Type Old Value New Value Added Description : Use of a Broken or Risky Cryptographic Algorithm vulnerability in Legion of the Bouncy Castle Inc. BC-JAVA bcpkix on all (pkix modules). PKIX draft CompositeVerifier accepts empty signature sequence as valid. This issue affects BC-JAVA: from 1.49 before 1.84. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/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 CWE CWE-327 Added Reference https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%905588
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.