Skip to main content
VulnerabilityPublished

CVE-2026-8674: The GNU C Library glibc · Reachable Assertion

Affects The GNU C Library glibcSource CVE Database V5

0
Compare

Not known to be exploited · CVSS 5.3 Medium.

Data as of 1 Nov 2026, 11:03 UTC

CVSS 3.1 base score
5.3Medium
How severe the flaw is on the 0–10 CVSS scale.
EPSS
0.3% chance of exploitation in 30 days – higher than 24% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Exploitation evidence

  1. Disclosed: evidence found.

    CVE published 17 Sep 2026

  2. Detectable: no evidence on record.

    No public nuclei template indexed

  3. Weaponized: no evidence on record.

    No public exploit code indexed in Metasploit or Exploit-DB

  4. Exploited in the wild: no evidence on record.

    Not in CISA KEV and no source reports exploitation

  5. Observed by OffSeq 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 1 Nov 2026.

What to do

Affected software

ProductAffectedFixed in
The GNU C LibraryglibcAffected
  • >=2.26 <=2.44
Fixed in–
Debiandebian/glibcpkg:deb/debian/glibcOther threatsAffected
  • >=2.26 <=2.44
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, administrators should monitor and control the length of DNS search domains configured via /etc/resolv.conf, DHCP, or VPN to avoid domains roughly 200 characters or longer. Network configuration software should validate and restrict such inputs to prevent triggering the assertion failure.

Description

CVE-2026-8674 is a reachable assertion vulnerability in the GNU C Library (glibc) affecting versions 2.26 through 2.44. It occurs when the DNS stub resolver initializes from an /etc/resolv.conf file or LOCALDOMAIN environment variable with a search list containing a domain roughly 200 characters or longer. This triggers an assertion failure that aborts the process. The flaw arises because the resolver truncates the search list into a fixed-size buffer but performs a consistency check against the wrong size, causing a valid truncated list to fail the assertion. Any process performing name resolution via glibc is affected, including long-running processes that reload /etc/resolv.conf after changes. Attackers on the local network may trigger this without privileges, leveraging DHCP or VPN server configurations that update search domains.

References

Community reviews

Loading reviews…