{"id":"CVE-2026-4437","title":"gethostbyaddr and gethostbyaddr_r may incorrectly handle DNS response","summary":"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 …","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","cvssSource":"adp","cwe":["CWE-125"],"vendor":"The GNU C Library","product":"glibc","affected":["glibc >= 2.34 <= 2.43"],"ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"partial","timestamp":"2026-03-23T15:10:34.650805Z"},"published":"2026-03-20","updated":"2026-10-15","sourceUpdated":"2026-10-15T01:12:09.122Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-4437","references":[{"url":"https://sourceware.org/bugzilla/show_bug.cgi?id=34014"}],"tags":["cve.org"],"epss":0.00325,"epssPercentile":0.23881,"ingestedAt":"2026-10-15T05:52:46.050Z","slug":"CVE-2026-4437","body":"## Overview\n\nCalling 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.\n\n## Affected\n\n- `glibc >= 2.34 <= 2.43`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}