CVE-2026-50643

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.

CVSS

No CVSS.

References

Link	Resource
https://cert.pl/en/posts/2026/06/CVE-2026-50641
https://github.com/rui314/8cc

Configurations

No configuration.

History

No history.

Information

Published : 2026-06-18 13:25

Updated : 2026-06-22 17:49

NVD link : CVE-2026-50643

Mitre link : CVE-2026-50643

CVE.ORG link : CVE-2026-50643

JSON object : View

Products Affected

No product.

CWE

CWE-125

Out-of-bounds Read

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