CVE-2026-13500 MEDIUM

CVE-2026-13500: antlr ANTLR4 Grammar Action Block OutputFile.java code injection

Vendor Antlr
Product ANTLR4
Weakness CWE-94 · Code injection
Published June 28, 2026
Last update June 29, 2026

CVSS base score

6.9/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality
Integrity

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

June 28, 2026 CVE published
June 29, 2026 Record updated