SIPGO is a library for writing SIP services in the GO language. Starting in version 0.3.0 and prior to version 1.0.0-alpha-1, a nil pointer dereference vulnerability is in the SIPGO library's `NewResponseFromRequest` function that affects all normal SIP operations. The vulnerability allows remote attackers to crash any SIP application by sending a single malformed SIP request without a To header. The vulnerability occurs when SIP message parsing succeeds for a request missing the To header, but the response creation code assumes the To header exists without proper nil checks. This affects routine operations like call setup, authentication, and message handling - not just error cases. This vulnerability affects all SIP applications using the sipgo library, not just specific configurations or edge cases, as long as they make use of the `NewResponseFromRequest` function. Version 1.0.0-alpha-1 contains a patch for the issue.
https://github.com/emiago/sipgo/security/advisories/GHSA-c623-f998-8hhv
https://github.com/emiago/sipgo/commit/dc9669364a154ec6d134e542f6a63c31b5afe6e8
Published: 2025-12-16
Updated: 2026-03-05
Base Score: 7.8
Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C
Severity: High
Base Score: 7.5
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Severity: High
Base Score: 8.7
Vector: 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
Severity: High
EPSS: 0.00555