antlr ANTLR4 up to 4.13.2 Grammar Action Block OutputFile.java code injection

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.6$0-$5k2.48

Summaryinfo

A vulnerability identified as critical has been detected in antlr ANTLR4 up to 4.13.2. Affected by this vulnerability is an unknown functionality of the file tool/src/org/antlr/v4/codegen/model/OutputFile.java of the component Grammar Action Block Handler. The manipulation leads to code injection. This vulnerability is referenced as CVE-2026-13500. Remote exploitation of the attack is possible. Furthermore, an exploit is available. The vendor was contacted early about this disclosure but did not respond in any way.

Detailsinfo

A vulnerability was found in antlr ANTLR4 up to 4.13.2 and classified as critical. This issue affects some unknown functionality of the file tool/src/org/antlr/v4/codegen/model/OutputFile.java of the component Grammar Action Block Handler. The manipulation with an unknown input leads to a code injection vulnerability. Using CWE to declare the problem leads to CWE-94. The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment. Impacted is confidentiality, integrity, and availability.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-13500. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details as well as a public exploit are known. The attack technique deployed by this issue is T1059 according to MITRE ATT&CK.

The exploit is available at github.com. It is declared as proof-of-concept. The vendor was contacted early about this disclosure but did not respond in any way.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 6.6

VulDB Base Score: 7.3
VulDB Temp Score: 6.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Code injection
CWE: CWE-94 / CWE-74 / CWE-707
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Access: Public
Status: Proof-of-Concept
Download: 🔒
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

06/27/2026 Advisory disclosed
06/27/2026 +0 days VulDB entry created
06/27/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Not defined

CVE: CVE-2026-13500 (🔒)
GCVE (CVE): GCVE-0-2026-13500
GCVE (VulDB): GCVE-100-374495
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 06/27/2026 20:33
Changes: 06/27/2026 20:33 (56)
Complete: 🔍
Submitter: jiazhou
Cache ID: 216::103

Submitinfo

Accepted

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