Dashboard / CVE-2026-56389

CVE-2026-56389

MEDIUM
MEDIUM Priority: 0.02 BB Relevance: 39/100
Published: 2026-07-29 Modified: 2026-10-23 First seen: 2026-10-29 Status: active

Attack Surface

Low Complexity No Auth Integ. Impact

CVSS Vector Breakdown

AV: Local
AC: Low
PR: None
UI: Active
S: X
AT: None
VC: None
VI: High
VA: Low

Description

GNU Bison allows for an execution of an arbitrary program during HTML report generation due to improper handling of grammar-defined configuration variables. A grammar file can override the executable used for the XML‑to‑HTML transformation step via %define tool.xsltproc, which is accepted without restriction and passed directly to execvp(). When running bison --html on a attacker-provided grammar, this behavior allows execution of an arbitrary program with the privileges of the Bison process. Maintainers of this project were notified about this vulnerability, and fixed the issue in commit 3169c1e7a2c6acc4c59dfcf8b089896d6881925b. However, they did not provide vulnerable version range. Version 3.8.2 was tested and confirmed as vulnerable, other versions were not tested but might also be vulnerable.

Weakness Classification (1)

Affected Software (1)

VendorProductVersion
gnu bison 3.8.2

References & Advisories (3)

Bug Bounty Relevance

39 / 100
✓ No authentication
✓ Low complexity

CVSS Score

6.8 / 10.0 v4.0
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:H/VA:L/SC:L/SI:L/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

EPSS — Exploitation Probability

0.22%
Raw Score 0.002240
Percentile 13.0%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00224
2026-10-28
0.00224

Intelligence Sources

nvd ref →

External Links