CVE-2026-19499
Buffer overflow in strfmon and strfmon_l right-justification padding
Description
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.
INFO
Published Date :
Sept. 14, 2026, 5:11 p.m.
Last Modified :
Sept. 14, 2026, 5:13 p.m.
Remotely Exploit :
Yes !
Source :
glibc
Affected Products
The following products are affected by CVE-2026-19499
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | 3ff69d7a-14f2-4f67-a097-88dee7810d18 |
Solution
- Update GNU C Library to a patched version.
- Review application code using strfmon functions.
- Avoid right-justified width padding in strfmon calls.
- Ensure output buffers are adequately sized.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
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The following list is the news that have been mention
CVE-2026-19499 vulnerability anywhere in the article.