CVE-2026-50643 MEDIUM

CVE-2026-50643: Out‑of‑Bounds Read in 8cc

Vendor Rui314
Product 8cc
Weakness CWE-125
Published June 18, 2026
Last update June 18, 2026

CVSS base score

5.1/10
Attack vector Local
Attack complexity Low
Privileges required None
User interaction None
Confidentiality
Integrity

CVSS vector

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

What the vulnerability does

01Description

8cc is vulnerable to an Out‑of‑Bounds Read due to improper handling of #line directives and GNU linemarkers. The compiler accepts attacker-controlled filename and line number metadata and later uses it without validation when accessing source line arrays. By supplying invalid or oversized line numbers, an attacker can trigger out-of-bounds memory access and a crash. Maintainer of this project was notified early about this vulnerability, but didn't respond with the details of vulnerability or vulnerable version range. Version corresponding to the commit b480958 was tested and confirmed as vulnerable, other versions were not tested but might also be vulnerable.

Key dates

02Disclosure timeline

June 18, 2026 CVE published