CVE-2026-57165

/// Technical description

PJSIP is a free and open source multimedia communication library written in C. Prior to commit 628b716, a stack buffer overflow exists in the PJLIB-UTIL telnet CLI front-end when redrawing the command line during history recall (handle_up_down() in cli_telnet.c). This affects only applications that enable the telnet CLI front-end (same gating as the related CLI issue). The line-redraw sequence for a recalled history entry can accumulate more data than a fixed-size stack buffer holds, which may lead to application termination. Exploitation requires access to the unauthenticated telnet CLI, which already permits arbitrary CLI commands, so the additional impact is limited. Applications that do not enable the telnet CLI front-end are not affected. This issue has been patched via commit 628b716.

/// Remediation

Check the references section for vendor advisories and patches from teluu. Update pjsip to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// Affected products

/// References