CVE-2026-8674

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{"bugzilla": {"description": "glibc: glibc DNS stub resolver: Denial of Service via long search domain in configuration", "id": "2536382", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2536382"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.3", "cvss3_scoring_vector": "CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-1025", "details": ["A flaw was found in the GNU C Library (glibc) DNS stub resolver. This vulnerability allows a remote attacker on the local network to cause a denial of service by providing a specially crafted, excessively long search domain. When the resolver attempts to initialize with this long domain from /etc/resolv.conf or the LOCALDOMAIN environment variable, it triggers an assertion failure, which aborts the process. This can be exploited without privileges on the target system, potentially through network configuration mechanisms like DHCP or a VPN server."], "name": "CVE-2026-8674", "package_state": [{"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "package_name": "glibc", "product_name": "Red Hat Hardened Images"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Fix deferred", "package_name": "openshift/ose-rhel-coreos-8", "product_name": "Red Hat OpenShift Container Platform 4"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Fix deferred", "package_name": "openshift/ose-rhel-coreos-9", "product_name": "Red Hat OpenShift Container Platform 4"}], "public_date": "2026-09-17T16:54:27Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-8674\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-8674\nhttps://joshua.hu/fuzzing-glibc-libresolv\nhttps://sourceware.org/bugzilla/show_bug.cgi?id=31026\nhttps://sourceware.org/git/?p=glibc.git;a=blob_plain;f=advisories/GLIBC-SA-2026-0021\nhttps://sourceware.org/git/?p=glibc.git;a=commit;h=506ea57086bfb9ce3daff1c14246a1cb532aba0a"], "threat_severity": "Moderate"}

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