CVE-2026-19499 (GCVE-0-2026-19499)
Vulnerability from cvelistv5 – Published: 2026-09-14 17:11 – Updated: 2026-09-14 19:40
VLAI
EPSS
VEX
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)
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
References
2 references
| URL | Tags |
|---|---|
| https://sourceware.org/bugzilla/show_bug.cgi?id=34510 | issue-tracking |
| https://sourceware.org/git/?p=glibc.git;a=blob_pl… | vendor-advisory |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| The GNU C Library | glibc |
Affected:
2.38 , ≤ 2.44
(custom)
|
guessed |
Date Public
2026-08-11 04:00
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