VDB
CVE-2026-4437
CVE-2026-4437
PUBLISHED
CVSS 7.5 HIGH
Calling gethostbyaddr or gethostbyaddr_r with a configured nsswitch.conf that specifies the library's DNS backend in the GNU C Library version 2.34 to version 2.43 could, with a crafted response from the configured DNS server, result in a violation of the DNS specification that causes the application to treat a non-answer section of the DNS response as a valid answer.
EPSS 0.09% · 25.4th percentile
Risk Scores
CVSS 3.1
7.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score
0.09%
25.4th percentile
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| The GNU C Library | glibc | 2.34, 2.34 |
| gnu | glibc | 2.34 |
Exploit Intelligence
- CIRCL seen: CVE-2026-4437 (circl-sighting)
- CIRCL seen: CVE-2026-4437 (circl-sighting)
- https://sourceware.org/bugzilla/show_bug.cgi?id=34014 (nist-nvd)
- CIRCL seen: CVE-2026-4437 (circl-sighting)
- CIRCL seen: CVE-2026-4437 (circl-sighting)
- CIRCL seen: CVE-2026-4437 (circl-sighting)
- dockerscan.yml (github-poc)
- sec-build.yaml (github-poc)
- dockerscan.yml (github-poc)
- dockerscan.yml (github-poc)
…and 11 more exploits
Timeline
- Mar 20, 2026 PoC Published
- Mar 20, 2026 CVE Published
- Mar 21, 2026 EPSS Score
- Mar 22, 2026 EPSS Score
- Mar 22, 2026 Coalition ESS Score
- Mar 23, 2026 EPSS Score
- Mar 23, 2026 Coalition ESS Score
- Mar 23, 2026 PoC Published
- Mar 24, 2026 EPSS Score
- Mar 24, 2026 Coalition ESS Score
- Mar 25, 2026 EPSS Score
- Mar 25, 2026 Coalition ESS Score
References
- https://sourceware.org/bugzilla/show_bug.cgi?id=34014 url
- https://nvd.nist.gov/vuln/detail/CVE-2026-4437 advisory
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-32748 advisory
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-4438 advisory
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-23347 advisory
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-23268 advisory
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-23392 advisory
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-23319 advisory
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-23253 advisory
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-23296 advisory
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-23364 advisory
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-23368 advisory
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-27654 advisory
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-30922 advisory
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-23286 advisory
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-23396 advisory
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-23340 advisory
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-23324 advisory
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-33515 advisory
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-23318 advisory
…and 59 more