CVE-2026-19499 (GCVE-0-2026-19499)

Vulnerability from cvelistv5 – Published: 2026-09-14 17:11 – Updated: 2026-09-14 19:40
VLAI
Title
Buffer overflow in strfmon and strfmon_l right-justification padding
Summary
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.
Severity
7.7 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-14 19:40 UTC
CWE
  • CWE-122 - Heap-based buffer overflow
Assigner
glibc CNA under the redhat root
CNA scorecard B 79/100 over 16 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
The GNU C Library glibc Affected: 2.38 , ≤ 2.44 (custom)
guessed Create a notification for this product.
Date Public
2026-08-11 04:00
Credits
AISLE in partnership with Red Hat
Show details on NVD website
To clipboard 

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