CVE-2026-57166

MEDIUM CVSS 4.0: 6.3 EPSS 0.53%
Updated Sep 11, 2026
Teluu
Parameter Value
CVSS 6.3 (MEDIUM)
Affected Versions before 2.17
Type CWE-121 (Stack-based Buffer Overflow)
Vendor Teluu
Public PoC No

PJSIP is a free and open source multimedia communication library written in C. Prior to commit 4472a31, a stack buffer overflow exists in the PJLIB-UTIL telnet CLI front-end when rendering feedback for an entered command line. Several command-line handling paths write an attacker-influenced amount of data into fixed-size buffers without sufficient bounds checking, so a long command line can overflow them.

This affects only applications that enable the telnet CLI front-end (e.g. pj_cli_telnet_create() / --cli-telnet-port). The telnet CLI is an interactive administration interface with no authentication, so any client able to reach it can already issue arbitrary CLI commands. A malformed or overly long command line can overflow a fixed-size stack buffer while rendering command-line feedback, which may lead to application termination.

Because reaching this code already requires access to the unauthenticated CLI, the impact beyond that existing access is limited. Applications that do not enable the telnet CLI front-end are not affected. This issue has been patched via commit 4472a31.

Attack Parameters

Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
Present
Additional conditions required
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed

Impact Assessment

Confidentiality
None
No data leak
Integrity
None
No data modification
Availability
Low
Partial disruption

CVSS Vector v4.0

Vulnerable Products 1

Configuration From (including) Up to (excluding)
Teluu Pjsip
cpe:2.3:a:teluu:pjsip:*:*:*:*:*:*:*:*
— <= 2.17