CVE-2026-19499

Calling strfmon and strfmon_l in the GNU C Library version 2.38 to 2.44 can write past the end of the caller-supplied output buffer when a conversion uses right-justified width padding. Exploitation requires an application code path that calls strfmon or strfmon_l with right-justified width padding into a destination buffer that is large enough for the padding to succeed but too small for the internal memmove call. The field width or format may be attacker-influenced or a fixed susceptible pattern in the caller. At the time of publication, no network-facing application impact is known.

CVSS v3 7.7 HIGH

7.7^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.5

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://sourceware.org/bugzilla/show_bug.cgi?id=34510
https://sourceware.org/git/?p=glibc.git;a=blob_plain;f=advisories/GLIBC-SA-2026-0017

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-14 18:17

Updated : 2026-09-14 20:16

NVD link : CVE-2026-19499

Mitre link : CVE-2026-19499

CVE.ORG link : CVE-2026-19499

JSON object : View

Products Affected

No product.

CWE

CWE-122

Heap-based Buffer Overflow

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