CVE-2026-57164PJSIP: Heap overflow in the HTTP client

PJSIP is a free and open source multimedia communication library written in C. Prior to commit 8d5956a, a heap buffer overflow exists in the PJLIB-UTIL HTTP client (http_client.c) when buffering an HTTP response body. This affects applications that use the PJLIB-UTIL HTTP client to receive a whole response body at once (a completion callback with no incremental on_data_read callback). When growing the response buffer, an incorrect size calculation based on the server-supplied Content-Length can leave the buffer too small, causing response data to be written past the end of the allocation. A malicious or man-in-the-middle HTTP server can trigger this with a crafted response; impact may range from unexpected application termination to memory corruption. Applications that consume the response incrementally (via on_data_read), or that only connect to trusted servers, are not affected. This issue has been patched via commit 8d5956a.

CVSS

8.3 HIGH (v4.0, CNA)CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N

Weakness (CWE)

CWE-122

Known exploited

Not in CISA's KEV catalog

EPSS (exploitation in the next 30 days)

Not loaded for this CVE

Assigned by

GitHub_M

NVD analysis

Analyzed

Record last updated

Sep 8, 2026

First seen by InfoSec Signals

Oct 9, 2026

The CVE record on cve.org · NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.