CVE-2018-16657

Severity: critical (CVSS 9.8 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 3.6% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2018-09-07 · updated 2026-06-17
Weakness: CWE-476

Description

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.

Affected products

Debian Linux: 8.0, 9.0
Kamailio: before 5.0.7; from 5.1.0 before 5.1.4 — fixed in 5.0.7, 5.1.4

How to fix

Upgrade to a fixed version: Kamailio 5.0.7, 5.1.4. Check the vendor advisory for mitigations.

References

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