{"id":"AZL-100019","summary":"CVE-2026-89092 affecting package glibc 2.38-21","details":"The nscd service in the GNU C Library 2.3.4 onwards may crash due to a \nstack overflow when a malicious DNS server returns too large a response \nfor a DNS query, resulting in degraded DNS resolution for the system.\n\n\n\nExploitation of this bug needs a system that has nscd enabled and using \nan untrusted DNS server for name resolution, with the compromised DNS \nserver being capable of processing records large enough to result in a \nstack overflow in an nscd thread stack.  During experimentation, bind 9 \nwas unable to handle large records, but that could change in future or \nwith a different name server.  In typical installations, nscd is \nexecuted in an isolated context as its own user without a shell, due to \nwhich any compromise of that service is isolated.\n\n\n\nThere is a remote possibility of nscd cache corruption if an attacker \nmanages to get the stack pointer into a desired point in the heap, \npotentially resulting in other caches in nscd being overwritten with \ncorrupt data through the stack overflow, until the buggy code path \neventually results in a crash.\n\n\n\nFinally, a crash in nscd may result in performance degradation when \nresolving names, but it does not result in a denial of service.","modified":"2026-09-12T05:27:53Z","published":"2026-09-11T02:18:35Z","upstream":["CVE-2026-89092"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89092"}],"affected":[{"package":{"name":"glibc","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/glibc"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"2.38-21"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-100019.json"}}],"schema_version":"1.9.0"}