Vulnerability in GNU Bison Affecting Assertion Functionality
CVE-2025-8733

4.8MEDIUM

Key Information:

Vendor

Gnu
Status
Bison
Vendor
CVE Published:
8 August 2025

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2025-8733?

A security issue has been identified in GNU Bison versions up to 3.8.2, specifically in the __obstack_vprintf_internal function within obprintf.c. This vulnerability allows for assertion failures that can be exploited locally, potentially leading to unwanted program behavior. The public disclosure has raised concerns regarding the safety of applications utilizing affected versions of Bison, making it crucial for users to address this issue promptly.

Affected Version(s)

Bison 3.8.0

Bison 3.8.1

Bison 3.8.2

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-2025-8733 - Proof of Concept

References

https://vuldb.com/?id.319229
vdb-entrytechnical-description
https://vuldb.com/?ctiid.319229
signaturepermissions-required
https://vuldb.com/?submit.622298
third-party-advisory

CVSS V4

Score:
4.8
Severity:
MEDIUM
Confidentiality:
None
Integrity:
None
Availability:
Low
Attack Vector:
Local
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

.
CVE-2025-8733 : Vulnerability in GNU Bison Affecting Assertion Functionality