Description
Calling the scanf family of functions with a %mc (malloc'd character match) in the GNU C Library version 2.7 to version 2.43 with a format width specifier with an explicit width greater than 1024 could result in a one byte heap buffer overflow.
Published: 2026-04-20
Score: 9.8 Critical
EPSS: < 1% Very Low
KEV: No
Impact: Heap Buffer Overflow (memory corruption)
Action: Patch glibc
AI Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

Remediation

No vendor fix or workaround currently provided.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

Sign in to view the affected projects.

Advisories

No advisories yet.

History

Thu, 23 Apr 2026 15:45:00 +0000

Type Values Removed Values Added
First Time appeared Gnu
Gnu glibc
Weaknesses CWE-787
CPEs cpe:2.3:a:gnu:glibc:*:*:*:*:*:*:*:*
Vendors & Products Gnu
Gnu glibc

Wed, 22 Apr 2026 12:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-131
References
Metrics threat_severity

None

threat_severity

Moderate


Wed, 22 Apr 2026 00:00:00 +0000

Type Values Removed Values Added
Metrics cvssV3_1

{'score': 9.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'}

ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Mon, 20 Apr 2026 23:15:00 +0000

Type Values Removed Values Added
First Time appeared The Gnu C Library
The Gnu C Library glibc
Vendors & Products The Gnu C Library
The Gnu C Library glibc

Mon, 20 Apr 2026 21:00:00 +0000

Type Values Removed Values Added
Description Calling the scanf family of functions with a %mc (malloc'd character match) in the GNU C Library version 2.7 to version 2.43 with a format width specifier with an explicit width greater than 1024 could result in a one byte heap buffer overflow.
Title scanf %mc off-by-one heap buffer overflow
Weaknesses CWE-122
References

Subscriptions

Gnu Glibc
The Gnu C Library Glibc
cve-icon MITRE

Status: PUBLISHED

Assigner: glibc

Published:

Updated: 2026-04-21T19:49:53.221Z

Reserved: 2026-04-02T21:47:21.403Z

Link: CVE-2026-5450

cve-icon Vulnrichment

Updated: 2026-04-21T16:04:17.997Z

cve-icon NVD

Status : Analyzed

Published: 2026-04-20T21:16:36.850

Modified: 2026-04-23T15:33:34.277

Link: CVE-2026-5450

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-04-20T20:55:41Z

Links: CVE-2026-5450 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-04-28T21:45:26Z

Weaknesses