CVE-2026-57166 (GCVE-0-2026-57166)

Vulnerability from cvelistv5 – Published: 2026-09-04 17:12 – Updated: 2026-09-09 16:03
VLAI
Title
PJSIP: Pre-authentication overflow in the telnet CLI error
Summary
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.
Severity
6.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-09 16:03 UTC
CWE
  • CWE-121 - Stack-based Buffer Overflow
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7746 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
pjsip pjproject Affected: < 4472a31d77a7506ff175dad5abef490f4e31bed1
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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