Quick answers
- Is CVE-2026-57165 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-57165 being exploited in the wild.
- How severe is CVE-2026-57165?
- Medium severity, with a CVSS score of 5.3, published 4 September 2026.
- Which products and versions are affected?
- PJSIP PJSIP 2.17 or lower.
- Is there a fix for CVE-2026-57165?
- A patch was published on 2026-06-17: Patch available as commit 628b716 in master branch Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-57165 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-57165?
- Check whether you run Teluu Pjsip. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
A stack buffer overflow exists in the handle_up_down() function in cli_telnet.c within PJLIB-UTIL, the utility library component of PJSIP. The vulnerability occurs when redrawing the command line during history recall: the function accumulates cur_pos + 2*rcmd->len + history->slen bytes into a fixed-size PJ_CLI_MAX_CMDBUF stack buffer without proper bounds checking. An unauthenticated attacker with access to the telnet CLI can craft a history entry that triggers the overflow, leading to application termination or potential code execution. The patch (commit 628b716) sizes the buffer for worst-case scenarios, clamps each term to PJ_CLI_MAX_CMDBUF, and replaces an unchecked pj_strcat with bounded pj_memcpy. This issue only affects applications that explicitly enable the telnet CLI front-end.
Affected products
- PJSIP PJSIP 2.17 or lower
Timeline
- 2026-09-04: disclosed
- 2026-06-17: patched: Patch available as commit 628b716 in master branch