Description
A vulnerability has been found in Kamailio 5.5. This affects the function yyerror_at of the file src/core/cfg.y of the component Grammar Rule Handler. Such manipulation leads to null pointer dereference. The attack needs to be performed locally. The exploit has been disclosed to the public and may be used. The actual existence of this vulnerability is currently in question. This attack requires manipulating config files which might not be a realistic scenario in many cases. The vendor was contacted early about this disclosure but did not respond in any way.
Affected products
kamailio: kamailio
References9
- shimo.im/docs/vVqRMVMlrycMO63y/ ExploitThird Party Advisory
- shimo.im/docs/vVqRMVMlrycMO63y ExploitThird Party Advisory
- vuldb.com/?ctiid.329877 Permissions RequiredVDB Entry
- vuldb.com/?id.329877 Third Party AdvisoryVDB Entry
- vuldb.com/?submit.673241 Third Party AdvisoryVDB Entry
- www.openwall.com/lists/oss-security/2025/11/02/3
- www.openwall.com/lists/oss-security/2025/10/27/12
- www.openwall.com/lists/oss-security/2025/10/27/8
- www.openwall.com/lists/oss-security/2025/10/27/8 Issue TrackingMailing List
Metrics
- CVSS 3.1
-
5.5
MEDIUM
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - CVSS 4.0
-
1.9
LOW
Score source: CNA
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 14 · as of 10 November 2026
- CWE
- CWE-404CWE-476
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