CVE-2023-27601

Published: 15 March 2023

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 has been fixed in versions 3.1.7 and 3.2.4.

Status

Severity score breakdown

References

• https://github.com/OpenSIPS/opensips/commit/8f87c7c03da55f9c79bd92e67fa2c94b2a7ce5cf
• https://github.com/OpenSIPS/opensips/security/advisories/GHSA-xj5x-g52f-548h
• https://opensips.org/docs/modules/3.3.x/sipmsgops.html
• https://opensips.org/pub/audit-2022/opensips-audit-technical-report-full.pdf
• https://www.cve.org/CVERecord?id=CVE-2023-27601
• NVD
• Launchpad
• Debian