Path Traversal Vulnerability in ANTLR4 TokenVocab Parsing Component by antlr
CVE-2026-13503

6.9MEDIUM

Key Information:

Vendor

Antlr

Status
Antlr4
Vendor
CVE Published:
28 June 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-13503?

A path traversal vulnerability exists in the getImportedVocabFile function of ANTLR4's TokenVocabParser.java, allowing attackers to manipulate file paths. This can potentially lead to unauthorized access to system files. The issue has been publicly disclosed, and remediation is crucial as it can be exploited remotely. The vendor has been notified but has not responded.

Affected Version(s)

ANTLR4 4.13.0

ANTLR4 4.13.1

ANTLR4 4.13.2

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2026-13503 - Proof of Concept

References

https://vuldb.com/vuln/374497
vdb-entrytechnical-description
https://vuldb.com/vuln/374497/cti
signaturepermissions-required
https://vuldb.com/cve/CVE-2026-13503
third-party-advisory

CVSS V4

Score:
6.9
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

jiazhou (VulDB User)
VulDB CNA Team
.