CVE-2026-5450

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.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://inbox.sourceware.org/libc-announce/b11f0003-6ec1-4bd6-b9de-9e38a4efeca3@redhat.com/T/#u	Third Party Advisory
https://sourceware.org/bugzilla/show_bug.cgi?id=CVE-2026-5450	Exploit Issue Tracking
https://cert-portal.siemens.com/productcert/html/ssa-082556.html
https://sourceware.org/bugzilla/show_bug.cgi?id=CVE-2026-5450	Exploit Issue Tracking

Configurations

Configuration 1 (hide)

cpe:2.3:a:gnu:glibc:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-04-20 21:16

Updated : 2026-07-14 13:19

NVD link : CVE-2026-5450

Mitre link : CVE-2026-5450

CVE.ORG link : CVE-2026-5450

JSON object : View

Products Affected

gnu

glibc

CWE

CWE-122

Heap-based Buffer Overflow

CWE-787

Out-of-bounds Write

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