Stack Overflow Vulnerability in GNU C Library's nscd Service
CVE-2026-89092

4.2MEDIUM

Key Information:

Vendor

The Gnu C Library

Status
Glibc
Vendor
CVE Published:
11 September 2026

What is CVE-2026-89092?

The nscd service within the GNU C Library versions 2.3.4 and higher is susceptible to a stack overflow condition when an untrusted DNS server replies with excessively large DNS response records. This vulnerability can lead to crashes of the nscd service, resulting in degraded DNS resolution performance. While exploitation of this flaw requires that nscd is enabled and configured to use untrusted DNS sources, successful exploitation may lead to cache corruption if an attacker can manipulate the stack pointer to overwrite crucial data within nscd's heap. Although such a crash can disrupt normal name resolution, it does not result in a complete denial of service.

Affected Version(s)

glibc 2.3.4 < 2.45

References

https://sourceware.org/bugzilla/show_bug.cgi?id=34624
issue-tracking
https://sourceware.org/git/?p=glibc.git;a=blob_plain;f=ad...
vendor-advisory

CVSS V3.1

Score:
4.2
Severity:
MEDIUM
Confidentiality:
None
Integrity:
Low
Availability:
None
Attack Vector:
Adjacent Network
Attack Complexity:
High
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Anmol Singh Rajput
.