Red Hat Security Advisory: compat-glibc security update
Affects Red Hat compat-glibcSource GCVE Database
Not known to be exploited · CVSS 9.8 Critical.
Data as of 3 Nov 2026, 20:58 UTC
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 20 Apr 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 3 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| The GNU C Libraryglibc | Affected
| Fixed in– |
Debiandebian/glibcpkg:deb/debian/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
Red Hat has released updated compat-glibc packages for Extended Life Cycle Support 7 to address this vulnerability. Users should apply the security update as described in the Red Hat advisory RHSA-2026:37396 and the referenced article https://access.redhat.com/articles/11258. No additional mitigation steps are indicated.
Description
A heap buffer overflow vulnerability exists in the GNU C Library (glibc) when using the scanf function with the %mc format specifier and a large width. This affects the compat-glibc package used for compatibility with Red Hat Enterprise Linux 6 libraries on Extended Life Cycle Support 7. The issue has been rated as moderate severity by Red Hat Product Security.