CVE-2026-19499

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.

Affected Software

VendorProductVersion RangeStatus
The GNU C Libraryglibc2.38 <= 2.44affected

Weaknesses

  • CWE-122: CWE-122 Heap-based buffer overflow

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References