{"id":"CVE-2026-8674","summary":"Assertion failure in the DNS stub resolver with a long search domain","details":"Initializing the DNS stub resolver from an /etc/resolv.conf file, or a LOCALDOMAIN environment variable, whose search list contains a domain of roughly 200 characters or more in the GNU C Library version 2.26 to 2.44 results in an assertion failure which aborts the process.\n\nThe resolver truncates the search list when copying it into the fixed-size _res.defdname buffer, then asserts that the copy is consistent with the full configuration.  The consistency check compared against the wrong size and did not handle a first entry that does not fit, so a correctly truncated list failed the assertion.  Any process that resolves names through the library is affected, including long-running processes that reload /etc/resolv.conf on the next query after it changes.  Search domains are commonly written to /etc/resolv.conf from data received over DHCP or from a VPN server, so an attacker on the local network may be able to trigger this without privileges on the target system, subject to validation by the network configuration software.","modified":"2026-09-18T03:48:34.352395895Z","published":"2026-09-17T16:54:27.310Z","database_specific":{"cna_assigner":"glibc","cwe_ids":["CWE-617"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/8xxx/CVE-2026-8674.json"},"references":[{"type":"WEB","url":"http://www.openwall.com/lists/oss-security/2026/09/17/4"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/8xxx/CVE-2026-8674.json"},{"type":"ARTICLE","url":"https://joshua.hu/fuzzing-glibc-libresolv"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-8674"},{"type":"REPORT","url":"https://sourceware.org/bugzilla/show_bug.cgi?id=31026"},{"type":"ADVISORY","url":"https://sourceware.org/git/?p=glibc.git;a=blob_plain;f=advisories/GLIBC-SA-2026-0021"},{"type":"FIX","url":"https://sourceware.org/git/?p=glibc.git;a=commit;h=506ea57086bfb9ce3daff1c14246a1cb532aba0a"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://sourceware.org/git/glibc.git","events":[{"introduced":"1c9a5c270d8b66f30dcfaf1cb2d6cf39d3e18369"},{"last_affected":"c3a3a9808ad3ab4a3336836833f83288b672ccbf"}],"database_specific":{"extracted_events":[{"introduced":"2.26"},{"last_affected":"2.44"}],"source":"AFFECTED_FIELD"}}],"versions":["glibc-2.44","glibc-2.43.9000","glibc-2.43","glibc-2.42","glibc-2.42.9000","glibc-2.41.9000","glibc-2.41","glibc-2.40","glibc-2.40.9000","glibc-2.39.9000","glibc-2.39","glibc-2.38","glibc-2.38.9000","glibc-2.37","glibc-2.37.9000","glibc-2.36","glibc-2.36.9000","glibc-2.35","glibc-2.35.9000","glibc-2.34","glibc-2.34.9000","glibc-2.33","glibc-2.33.9000","glibc-2.32","glibc-2.32.9000","glibc-2.31","glibc-2.31.9000","changelog-ends-here","glibc-2.30","glibc-2.30.9000","glibc-2.29","glibc-2.29.9000","glibc-2.28","glibc-2.28.9000","glibc-2.27","glibc-2.27.9000","glibc-2.26","glibc-2.26.9000"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-8674.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}