Calling the wide scanf family of functions (swscanf, fwscanf, wscanf, vswscanf, vfwscanf and vwscanf) with a %s or %[
Source GCVE Database
Not known to be exploited · CVSS 4.8 Medium.
Data as of 11 Nov 2026, 20:03 UTC
Thin evidence
One scorer or none| CNA (glibc) | CVSS 3.1 | 4.8 |
|---|
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:LExploitation evidence
Disclosed: evidence found.
CVE published 11 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 11 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| The GNU C Libraryglibc | Affected
| Fixed in– |
Gnugnu/glibcpkg:rpm/gnu/glibcOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Until a fix is available, avoid using the affected wide scanf functions with %s or %[ conversions without the 'l' length modifier on untrusted input, or ensure destination buffers are sized to accommodate an extra null byte to prevent overflow.
Description
A vulnerability in the GNU C Library versions 2.2 through 2.44 affects the wide scanf family of functions when called with %s or %[ conversions without the 'l' length modifier. This causes an extra null byte to be written just past the end of the destination array if the converted multibyte string exactly fills the buffer. The overflow byte is always a null byte, which can corrupt adjacent memory or cause a crash. This issue affects all architectures and ABIs supported by the GNU C Library. Narrow scanf functions and other related conversions are not affected.