{"id":"CVE-2021-26717","details":"An issue was discovered in Sangoma Asterisk 16.x before 16.16.1, 17.x before 17.9.2, and 18.x before 18.2.1 and Certified Asterisk before 16.8-cert6. When re-negotiating for T.38, if the initial remote response was delayed just enough, Asterisk would send both audio and T.38 in the SDP. If this happened, and the remote responded with a declined T.38 stream, then Asterisk would crash.","modified":"2026-02-11T14:27:12.712216Z","published":"2021-02-18T20:15:12.667Z","references":[{"type":"ADVISORY","url":"http://packetstormsecurity.com/files/161471/Asterisk-Project-Security-Advisory-AST-2021-002.html"},{"type":"ADVISORY","url":"http://seclists.org/fulldisclosure/2021/Feb/58"},{"type":"ADVISORY","url":"https://downloads.asterisk.org/pub/security/"},{"type":"ADVISORY","url":"https://downloads.asterisk.org/pub/security/AST-2021-002.html"},{"type":"ADVISORY","url":"https://issues.asterisk.org/jira/browse/ASTERISK-29203"},{"type":"REPORT","url":"https://issues.asterisk.org/jira/browse/ASTERISK-29203"},{"type":"FIX","url":"http://seclists.org/fulldisclosure/2021/Feb/58"},{"type":"FIX","url":"https://issues.asterisk.org/jira/browse/ASTERISK-29203"},{"type":"ARTICLE","url":"http://seclists.org/fulldisclosure/2021/Feb/58"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/asterisk/asterisk","events":[{"introduced":"2c1bba3cbec008c8ce35c78a2c79f9f207ea58bc"},{"fixed":"332130c4389803a3c7e63cabf00daf5ac66a3068"},{"introduced":"5ffe12b6ef30cd503f85d75745fd8d9c2cfafe47"},{"fixed":"fdaf2d0689b7a8928a45019c9af14c53bcdfa6e3"},{"introduced":"a65908f83e2f17a3aca7eb39c8e06045aca02674"},{"fixed":"3cd8afbdf2c6dffe80c631a5336e21bb1827a5cd"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2021-26717.json"}}],"schema_version":"1.7.3","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}