NULL pointer dereference in Kamailio

CVE-2025-12207

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.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 3.3 (Low). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L.

EPSS exploit prediction

EPSS: 0.002 (12.7th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 13th percentile — 12.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2025-12207: held from 0.002 to 0.002.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000

Affected products

  • Kamailio — versions 5.5.0
  • Kamailio — versions 5.5

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-12207?
CVE-2025-12207 is a low-severity vulnerability in Kamailio, classified under Improper Resource Shutdown or Release. CVSS score: 3.3/10. Published 2025-10-27.
How severe is CVE-2025-12207?
Low severity. CVSS v3 base score is 3.3 out of 10.