Out‑of‑Bounds Read in 8cc_CVE-2026-50643

5.1 / 10

MEDIUM

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

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.

Basic Information

ID CVE-2026-50643

Source CERT-PL

Published Jun 18, 2026 at 08:58

Modified Jun 18, 2026 at 12:29

Affected Product

Vendor rui314

Product 8cc

Version b480958

Affected Versions rui314 8cc b480958

CWE Classification

CWE-125

References

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    "description": "8cc is vulnerable to an Out\u2011of\u2011Bounds 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.\nBy supplying invalid or oversized line numbers, an attacker can trigger out-of-bounds memory access and a crash.\n\nMaintainer 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.",
    "published": "2026-06-18T08:58:01.908Z",
    "modified": "2026-06-18T12:29:43.415Z",
    "type": "cve",
    "title": "Out\u2011of\u2011Bounds Read in 8cc",
    "source": "CERT-PL",
    "references": "https://cert.pl/en/posts/2026/06/CVE-2026-50641\nhttps://github.com/rui314/8cc",
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