Vulnerability CVE-2023-27600
Published: 2023-03-15   Modified: 2023-03-16

Description:
OpenSIPS is a Session Initiation Protocol (SIP) server implementation. Prior to versions 3.1.7 and 3.2.4, OpenSIPS crashes when a malformed SDP body is received and is processed by the `delete_sdp_line` function in the sipmsgops module. This issue can be reproduced by calling the function with an SDP body that does not terminate by a line feed (i.e. `\n`). The vulnerability was found while performing black-box fuzzing against an OpenSIPS server running a configuration that made use of the functions `codec_delete_except_re` and `codec_delete_re`. The same issue was also discovered while performing coverage guided fuzzing on the function `codec_delete_except_re`. The crash happens because the function `delete_sdp_line` expects that an SDP line is terminated by a line feed (`\n`). By abusing this vulnerability, an attacker is able to crash the server. It affects configurations containing functions that rely on the affected code, such as the function `codec_delete_except_re`. Due to the sanity check that is performed in the `del_lump` function, exploitation of this issue will generate an `abort` in the lumps processing function, resulting in a Denial of Service. This issue is patched in versions 3.1.7 and 3.2.4.

Type:

CWE-20

 (Improper Input Validation)

 References:
https://github.com/OpenSIPS/opensips/security/advisories/GHSA-67w7-g4j8-3wcx
https://github.com/OpenSIPS/opensips/commit/c6ab3bb406c447e30c7d33a1a8970048b4612100
https://opensips.org/docs/modules/3.3.x/sipmsgops.html
https://opensips.org/pub/audit-2022/opensips-audit-technical-report-full.pdf
Copyright 2026, cxsecurity.com

 

Back to Top