CVE-2018-16657
CVSS v3
9.8
CRITICAL
EPSS Score
3.6 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
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.
Technical details
- Published
- 2018-09-07
Frequently asked questions
What is CVE-2018-16657?
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.
Is CVE-2018-16657 actively exploited?
Active exploitation of CVE-2018-16657 has not been confirmed. Its EPSS score was 3.6% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2018-16657?
CVE-2018-16657 has a CVSS v3 base score of 9.8 (CRITICAL severity).
Is CVE-2018-16657 affecting your environment?
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