In Kamailio before 5.0.7 and 5.1.x before 5.1.4, a crafted SIP message with an invalid Via header causes a segmentation fault and crashes K…

published 2018-09-07 8 y ago modified 2026-06-17 4 mo ago also EUVD-2018-8459

cvss: 9.8; version 3.0, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 3.6%; EPSS 3.6% chance of exploitation in 30 days, percentile 89%
public exploits: 0; none known

In Kamailio before 5.0.7 and 5.1.x before 5.1.4, a crafted SIP message with an invalid Via header causes a segmentation fault and crashes Kamailio. The reason is missing input validation in the crcitt_string_array core function for calculating a CRC hash for To tags. (An additional error is present in the check_via_address core function: this function also misses input validation.) This could result in denial of service and potentially the execution of arbitrary code.

Patch / fix

fixed in 1 distros 2 links 1

kamailio kamailio 5.0.7, 5.1.4

debian ubuntu

kamailio Debian 14, Debian 13, Debian 12 5.1.4-1

debian advisories DEBIAN-CVE-2018-16657

kamailio Ubuntu Pro 16.04 LTS 4.3.4-1.1ubuntu2.1+esm1
kamailio Ubuntu Pro 18.04 LTS 5.1.2-1ubuntu2+esm1

ubuntu advisories UBUNTU-CVE-2018-16657

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

skalatan.de/blog/advisory-hw-2018-06 advisory

Exploit prediction

3.58% chance of exploitation in the next 30 days, higher than 89% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

skalatan.de https://skalatan.de/blog/advisory-hw-2018-06 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
NVD	3.0	9.8	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	7.5	AV:N/AC:L/Au:N/C:P/I:P/A:P

Classification

Weakness

CWE-476 NULL Pointer Dereference

References

skalatan.de /blog/advisory-hw-2018-06
exploit, patch, third-party-advisory
debian.org /security/2018/dsa-4292
vendor-advisory, third-party-advisory
lists.debian.org /debian-lts-announce/2018/09/msg00013.html
mailing-list, third-party-advisory

Sources

CVE List CVE-2018-16657
NVD CVE-2018-16657

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary