{"id":"CVE-2026-89147","summary":"Net-SNMP through 5.9.5.2 Denial of Service via Blocking Unauthenticated SMUX Read","details":"Net-SNMP through 5.9.5.2 contains a denial of service vulnerability in the SMUX module where smux_accept() performs an unauthenticated blocking read without timeout on newly accepted connections. An unauthenticated remote client can connect to the SMUX listener and send no data, causing the single-threaded snmpd main loop to block indefinitely and suspend all SNMP processing.","modified":"2026-09-13T03:47:19.070063206Z","published":"2026-09-11T10:46:56.944Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89147.json","cna_assigner":"VulnCheck","cwe_ids":["CWE-1088","CWE-400"]},"references":[{"type":"ADVISORY","url":"https://gist.github.com/thesmartshadow/001cea595e75fed6aaea7389666dc9eb"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89147.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89147"},{"type":"ADVISORY","url":"https://www.vulncheck.com/advisories/net-snmp-through-5.9.5.2-denial-of-service-via-blocking-unauthenticated-smux-read"},{"type":"PACKAGE","url":"https://github.com/net-snmp/net-snmp"},{"type":"ARTICLE","url":"https://github.com/net-snmp/net-snmp/blob/v5.9.5.2/agent/mibgroup/smux/smux.c"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/net-snmp/net-snmp","events":[{"introduced":"0"},{"fixed":"319bbd0bb36547992c0e1302fef278c6f49d0c80"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"last_affected":"5.9.5.2"},{"fixed":"5.9.5.2"}],"source":["AFFECTED_FIELD","DESCRIPTION"]}}],"versions":["v5.9.5.1","v5.9.5","v5.9.4","v5.9.4.rc1","v5.9.4.pre3","v5.9.4.pre2","v5.9.2","v5.9.2.rc2","v5.9.2.rc1","v5.9.2.pre1","v5.9.1","v5.9.1.rc1","v5.9.1.pre1","v5.9.verfix","v5.9","v5.9.rc2","v5.8.1.rc1","v5.8.1.pre2","v5.8.1.pre1","v5.8","v5.8.rc4","v5.8.rc3","v5.8.rc2","v5.8.rc1","v5.8.pre3","v5.8.pre2","v5.8.pre1","v5.7","v5.7.rc3","v5.7.rc2","v5.7.rc1","v5.7.pre2","v5.7.pre1","v5.6","v5.6.rc3","v5.6.rc2","v5.6.rc1","v5.6.pre3","v5.6.pre2","v5.6.pre1","v5.5","v5.5.rc3","v5.5.rc2","v5.5.rc1","v5.5.pre3","v5.5.pre2","v5.5.pre1","v5.1.4.1","v5.0.11.1","v5.4","v5.3","v5.2","v5.1","v5.0.7","v5.0.6","v5.0.5","v5.0.4","v5.0.3","v5.0.2","v5.0.1","v5.0","v4.2","v4.1.1","v4.1","v4.0.1","v4.0","v3.6.1","v3.6","v3.5","v3.4","v3.3","v3.2","v3.1.3","v3.1.2.1","v3.1.2","v3.1.1","v3.1.0.1","v3.1","v3.0.7.2","v3.0.7.1","v3.0.7","v3.0.6","v3.0.5","v3.0.4","v3.0.3","v3.0.2.1","v3.0.2","v3.0.1","v3.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-89147.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"}]}