CVE-2026-50643 | 8cc is vulnerable to an Out‑of‑Bounds Read due to improper h… | CVSS 5.1 MEDIUM

Description

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.

Metadata

CVE ID: CVE-2026-50643
State: PUBLISHED
Assigner: CERT-PL
Reserved: 2026-06-05 13:27 UTC
Published: 2026-06-18 08:58 UTC
Last updated: 2026-06-18 12:29 UTC
Primary CWE: CWE-125
CWE-125 Out-of-bounds Read
Vendor / Product: rui314 / 8cc
Sources: cve.org · NVD

Severity & Metrics

5.1 MEDIUM CVSS 4.0

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

SSVC — CISA Coordinator

Exploitation: none
Automatable: no
Tech. Impact: partial

Affected products (1)

Vendor	Product	Platform	Versions
rui314	8cc	—	b480958

Weakness (CWE)

CWE	Source	Description
CWE-125	cna	CWE-125 Out-of-bounds Read

CVSS scores (1)

Score	Severity	Version	Source	Vector
5.1	MEDIUM	4.0	cna	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

References (2)