CVE-2026-5450 | Calling the scanf family of functions with a %mc (malloc'd c… | CVSS 9.8 CRITICAL

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.

Metadata

CVE ID: CVE-2026-5450
State: PUBLISHED
Assigner: glibc
Reserved: 2026-04-02 21:47 UTC
Published: 2026-04-20 20:55 UTC
Last updated: 2026-04-21 19:49 UTC
Primary CWE: CWE-122
CWE-122 Heap-based buffer overflow
Vendor / Product: The GNU C Library / glibc
Sources: cve.org · NVD

Severity & Metrics

9.8 CRITICAL CVSS 3.1

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

SSVC — CISA Coordinator

Exploitation: PoC
Automatable: yes
Tech. Impact: total

Affected products (1)

Vendor	Product	Platform	Versions
The GNU C Library	glibc	—	2.7 < *

Weakness (CWE)

CWE	Source	Description
CWE-122	cna	CWE-122 Heap-based buffer overflow

CVSS scores (1)

Score	Severity	Version	Source	Vector
9.8	CRITICAL	3.1	adp	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References (2)