{"id":86894,"date":"2026-04-07T22:20:28","date_gmt":"2026-04-07T22:20:28","guid":{"rendered":""},"modified":"-0001-11-30T00:00:00","modified_gmt":"-0001-11-30T00:00:00","slug":"cve-2025-57767-asterisk-vulnerability-affecting-sip-request-authentication","status":"publish","type":"post","link":"https:\/\/www.ameeba.com\/blog\/cve-2025-57767-asterisk-vulnerability-affecting-sip-request-authentication\/","title":{"rendered":"CVE-2025-57767: Asterisk Vulnerability Affecting SIP Request Authentication<\/strong>"},"content":{"rendered":"

Overview<\/strong><\/p>\n

The CVE-2025-57767 is a critical vulnerability in the Asterisk open-source PBX and telephony toolkit. Specifically affecting the SIP request authentication process, this bug could potentially lead to system compromise or data leakage if exploited. Given the widespread use of the Asterisk system, this vulnerability puts numerous businesses and individuals at risk worldwide.<\/p>\n

Vulnerability Summary<\/strong><\/p>\n

CVE ID: CVE-2025-57767
\nSeverity: High (7.5 CVSS)
\nAttack Vector: Network
\nPrivileges Required: None
\nUser Interaction: None
\nImpact: System compromise and potential data leakage<\/p>\n

Affected Products<\/strong><\/p>\n

Product | Affected Versions<\/p>\n

Asterisk PBX | <20.15.2\nAsterisk PBX | <21.10.2\nAsterisk PBX | <22.5.2\n\nHow the Exploit Works<\/strong><\/p>\n

The vulnerability lies within the get_authorization_header() function in res_pjsip_authenticator_digest. When a SIP request with an Authorization header containing a realm not previously included in a 401 response’s WWW-Authenticate header is received, or if an incorrect realm is received without a previous 401 response sent, the function returns a NULL. This return value is not appropriately checked before attempting to retrieve the digest algorithm, causing a SEGV, or segmentation fault. This could then be exploited by an attacker to compromise the system or leak data.<\/p>\n

Conceptual Example Code<\/strong><\/p>\n

The malicious attacker might exploit the vulnerability by sending a SIP request with a manipulated Authorization header. This could look something like this:<\/p>\n

INVITE sip:target@example.com SIP\/2.0\nVia: SIP\/2.0\/UDP attacker.com;branch=z9hG4bK74bf9\nFrom: \"Attacker\" ;tag=9fxced76sl\nTo: \nCall-ID: 3848276298220188511@attacker.com\nCSeq: 2 INVITE\nAuthorization: Digest username=\"user\",realm=\"manipulated_realm\",nonce=\"abc123\",uri=\"sip:target@example.com\",response=\"...\",algorithm=MD5\nContent-Length: 0<\/code><\/pre>\n
In this request, the ‘realm’ parameter in the Authorization header would be manipulated to an incorrect value, triggering the vulnerability.<\/p>\n","protected":false},"excerpt":{"rendered":"
Overview The CVE-2025-57767 is a critical vulnerability in the Asterisk open-source PBX and telephony toolkit. Specifically affecting the SIP request authentication process, this bug could potentially lead to system compromise or data leakage if exploited. Given the widespread use of the Asterisk system, this vulnerability puts numerous businesses and individuals at risk worldwide. Vulnerability Summary […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"footnotes":""},"categories":[],"tags":[],"vendor":[],"product":[],"attack_vector":[],"asset_type":[],"severity":[],"exploit_status":[],"class_list":["post-86894","post","type-post","status-publish","format-standard","hentry"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t