CVE-2026-13500: Code Injection in antlr ANTLR4
A weakness has been identified in antlr ANTLR4 up to 4.13.2. Affected is an unknown function of the file tool/src/org/antlr/v4/codegen/model/OutputFile.java of the component Grammar Action Block Handler. Executing a manipulation can lead to code injection. The attack may be launched remotely. The exploit has been made available to the public and could be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.
AI Analysis
Technical Summary
CVE-2026-13500 identifies a code injection vulnerability in antlr ANTLR4 up to version 4.13.2, specifically in an unknown function of the file tool/src/org/antlr/v4/codegen/model/OutputFile.java within the Grammar Action Block Handler component. This flaw enables remote attackers to execute arbitrary code by manipulating the vulnerable function. The vulnerability is rated medium severity with a CVSS 4.0 score of 6.9 (AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P). Public exploit code exists, but no official patch or vendor response has been provided as of the publication date.
Potential Impact
Successful exploitation of this vulnerability can lead to remote code execution on systems using affected ANTLR4 versions. This can compromise the confidentiality, integrity, and availability of the affected system. The vulnerability is exploitable without authentication and requires no user interaction, increasing its risk. However, the overall severity is medium, reflecting some limitations in impact or exploit complexity.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no official fix or vendor response is available, users should consider applying workarounds such as restricting access to the vulnerable component or avoiding untrusted input in the Grammar Action Block Handler until a patch is released.
CVE-2026-13500: Code Injection in antlr ANTLR4
Description
A weakness has been identified in antlr ANTLR4 up to 4.13.2. Affected is an unknown function of the file tool/src/org/antlr/v4/codegen/model/OutputFile.java of the component Grammar Action Block Handler. Executing a manipulation can lead to code injection. The attack may be launched remotely. The exploit has been made available to the public and could be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.
CVSS v4.0
Score 6.9medium
Affected software
pkg:maven/org.antlr/antlr4cpe:2.3:a:antlr:antlr4:*:*:*:*:*:*:*:*Run on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-13500 identifies a code injection vulnerability in antlr ANTLR4 up to version 4.13.2, specifically in an unknown function of the file tool/src/org/antlr/v4/codegen/model/OutputFile.java within the Grammar Action Block Handler component. This flaw enables remote attackers to execute arbitrary code by manipulating the vulnerable function. The vulnerability is rated medium severity with a CVSS 4.0 score of 6.9 (AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P). Public exploit code exists, but no official patch or vendor response has been provided as of the publication date.
Potential Impact
Successful exploitation of this vulnerability can lead to remote code execution on systems using affected ANTLR4 versions. This can compromise the confidentiality, integrity, and availability of the affected system. The vulnerability is exploitable without authentication and requires no user interaction, increasing its risk. However, the overall severity is medium, reflecting some limitations in impact or exploit complexity.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no official fix or vendor response is available, users should consider applying workarounds such as restricting access to the vulnerable component or avoiding untrusted input in the Grammar Action Block Handler until a patch is released.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulDB
- Date Reserved
- 2026-06-27T18:27:58.576Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a41317827e9c79719150c0a
Added to database: 06/28/2026, 14:36:40 UTC
Last enriched: 07/05/2026, 23:27:25 UTC
Last updated: 08/12/2026, 15:28:14 UTC
Views: 388
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