{"api_version":"1","generated_at":"2026-09-19T07:37:44+00:00","cve":"CVE-2026-8674","urls":{"html":"https://cve.report/CVE-2026-8674","api":"https://cve.report/api/cve/CVE-2026-8674.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-8674","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-8674"},"summary":{"title":"Assertion failure in the DNS stub resolver with a long search domain","description":"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.","state":"PUBLISHED","assigner":"glibc","published_at":"2026-09-17 17:16:53","updated_at":"2026-09-18 18:17:47"},"problem_types":["CWE-617","CWE-617 CWE-617 Reachable Assertion"],"metrics":[{"version":"3.1","source":"3ff69d7a-14f2-4f67-a097-88dee7810d18","type":"Secondary","score":"5.3","severity":"MEDIUM","vector":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":5.3,"baseSeverity":"MEDIUM","attackVector":"ADJACENT_NETWORK","attackComplexity":"HIGH","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"}},{"version":"3.1","source":"CNA","type":"CVSS","score":"5.3","severity":"MEDIUM","vector":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","data":{"attackComplexity":"HIGH","attackVector":"ADJACENT_NETWORK","availabilityImpact":"HIGH","baseScore":5.3,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}}],"references":[{"url":"https://sourceware.org/git/?p=glibc.git;a=blob_plain;f=advisories/GLIBC-SA-2026-0021","name":"https://sourceware.org/git/?p=glibc.git;a=blob_plain;f=advisories/GLIBC-SA-2026-0021","refsource":"3ff69d7a-14f2-4f67-a097-88dee7810d18","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"http://www.openwall.com/lists/oss-security/2026/09/17/4","name":"http://www.openwall.com/lists/oss-security/2026/09/17/4","refsource":"af854a3a-2127-422b-91ae-364da2661108","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://sourceware.org/git/?p=glibc.git;a=commit;h=506ea57086bfb9ce3daff1c14246a1cb532aba0a","name":"https://sourceware.org/git/?p=glibc.git;a=commit;h=506ea57086bfb9ce3daff1c14246a1cb532aba0a","refsource":"3ff69d7a-14f2-4f67-a097-88dee7810d18","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://joshua.hu/fuzzing-glibc-libresolv","name":"https://joshua.hu/fuzzing-glibc-libresolv","refsource":"3ff69d7a-14f2-4f67-a097-88dee7810d18","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://sourceware.org/bugzilla/show_bug.cgi?id=31026","name":"https://sourceware.org/bugzilla/show_bug.cgi?id=31026","refsource":"3ff69d7a-14f2-4f67-a097-88dee7810d18","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-8674","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-8674","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"The GNU C Library","product":"glibc","version":"affected 2.26 2.44 custom","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[{"source":"CNA","value":"Joshua Rogers","lang":"en"}],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"8674","cve":"CVE-2026-8674","epss":"0.003060000","percentile":"0.236050000","score_date":"2026-09-18","updated_at":"2026-09-19 00:06:16"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"adp":[{"metrics":[{"other":{"content":{"id":"CVE-2026-8674","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","timestamp":"2026-09-17T18:05:54.714741Z","version":"2.0.3"},"type":"ssvc"}}],"providerMetadata":{"dateUpdated":"2026-09-17T18:06:00.631Z","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP"},"title":"CISA ADP Vulnrichment"},{"providerMetadata":{"dateUpdated":"2026-09-17T18:09:16.072Z","orgId":"af854a3a-2127-422b-91ae-364da2661108","shortName":"CVE"},"references":[{"url":"http://www.openwall.com/lists/oss-security/2026/09/17/4"}],"title":"CVE Program Container"}],"cna":{"affected":[{"defaultStatus":"unaffected","product":"glibc","vendor":"The GNU C Library","versions":[{"lessThanOrEqual":"2.44","status":"affected","version":"2.26","versionType":"custom"}]}],"credits":[{"lang":"en","type":"finder","value":"Joshua Rogers"}],"datePublic":"2023-11-07T05:00:00.000Z","descriptions":[{"lang":"en","supportingMedia":[{"base64":false,"type":"text/html","value":"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.<br><br>The 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."}],"value":"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."}],"metrics":[{"cvssV3_1":{"attackComplexity":"HIGH","attackVector":"ADJACENT_NETWORK","availabilityImpact":"HIGH","baseScore":5.3,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-617","description":"CWE-617 Reachable Assertion","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-09-17T16:54:27.310Z","orgId":"3ff69d7a-14f2-4f67-a097-88dee7810d18","shortName":"glibc"},"references":[{"tags":["issue-tracking"],"url":"https://sourceware.org/bugzilla/show_bug.cgi?id=31026"},{"tags":["vendor-advisory"],"url":"https://sourceware.org/git/?p=glibc.git;a=blob_plain;f=advisories/GLIBC-SA-2026-0021"},{"tags":["patch"],"url":"https://sourceware.org/git/?p=glibc.git;a=commit;h=506ea57086bfb9ce3daff1c14246a1cb532aba0a"},{"tags":["technical-description"],"url":"https://joshua.hu/fuzzing-glibc-libresolv"}],"source":{"discovery":"EXTERNAL"},"title":"Assertion failure in the DNS stub resolver with a long search domain","x_generator":{"engine":"Vulnogram 1.0.5"}}},"cveMetadata":{"assignerOrgId":"3ff69d7a-14f2-4f67-a097-88dee7810d18","assignerShortName":"glibc","cveId":"CVE-2026-8674","datePublished":"2026-09-17T16:54:27.310Z","dateReserved":"2026-05-15T12:15:59.229Z","dateUpdated":"2026-09-17T18:09:16.072Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-17 17:16:53","lastModifiedDate":"2026-09-18 18:17:47","problem_types":["CWE-617","CWE-617 CWE-617 Reachable Assertion"],"metrics":{"cvssMetricV31":[{"source":"3ff69d7a-14f2-4f67-a097-88dee7810d18","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":5.3,"baseSeverity":"MEDIUM","attackVector":"ADJACENT_NETWORK","attackComplexity":"HIGH","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":1.6,"impactScore":3.6}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-09-17T18:05:54.714741Z","id":"CVE-2026-8674","options":[{"exploitation":"none"},{"automatable":"no"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"8674","Ordinal":"1","Title":"Assertion failure in the DNS stub resolver with a long search do","CVE":"CVE-2026-8674","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"8674","Ordinal":"1","NoteData":"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.","Type":"Description","Title":"Assertion failure in the DNS stub resolver with a long search do"}]}}}