Integer underflow in pjsip - #VU165886
Published: November 11, 2026
Vulnerability identifier: #VU165886
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-191
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to abort the application process and cause a denial of service.
The vulnerability exists due to integer underflow in pjsua-lib's SIP INFO DTMF parser when incorrect body-length handling produces a negative remaining length with assertions enabled and DTMF callbacks configured. A remote attacker can send a single INFO request containing an improperly terminated application/dtmf-relay body during an established call to trigger an assertion failure and terminate the process.
Affected software
pjsip
Remediation
Install security update from vendor's website.
pjsip - update to 2.18