CVE-2026-57161
Received
Received - Intake
Stack Buffer Overflow in PJSIP Library
Vulnerability report for CVE-2026-57161, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-09-04
Last updated on: 2026-09-04
Assigner: GitHub, Inc.
Description
Description
PJSIP is a free and open source multimedia communication library written in C. Prior to commit acc03b5, a stack buffer overflow exists in PJSUA when processing Service-Route headers in a registration response (update_service_route() in pjsua_acc.c). This affects applications that register using the PJSUA/PJSUA2 account API (the default registration path). The Service-Route URIs from a 2xx response to REGISTER are stored into a fixed-size array without bounding the number of headers; a registrar that returns an excessive number of Service-Route headers can write past the end of the array on the stack. The values written are internal pointers rather than arbitrary data, so the most likely impact is unexpected application termination (denial of service), though memory corruption cannot be excluded. The malicious response may come from a compromised or malicious registrar, or — over unprotected transports — a spoofed response. This issue has been patched via commit acc03b5.
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| pjsip | pjsip | to acc03b5 (exc) |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-121 | A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function). |
