# CVE-2026-40892: PJSIP is a free and open source multimedia communication library written in C. In 2.16 and earlier, a stack buffer…

Source: https://junglewise.ai/threats/cve-2026-40892-pjsip-is-a-free-and-open-source-multimedia-communication-library  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-04-21  
License: CC BY 4.0 with a link back

CVE-2026-40892 · Severity: critical · CVSS 9.8 · Published 2026-04-21

PJSIP is a free and open source multimedia communication library written in C. In 2.16 and earlier, a stack buffer overflow exists in pjsip_auth_create_digest2() in PJSIP when using pre-computed digest credentials (PJSIP_CRED_DATA_DIGEST). The function copies credential data using cred_info->data.slen as the length without an upper-bound check, which can overflow the fixed-size ha1 stack buffer (128 bytes) if data.slen exceeds the expected digest string length.

Technologies: [PJSIP](https://junglewise.ai/threats/technologies/pjsip-pjsip). Vendors: [PJSIP](https://junglewise.ai/threats/vendors/pjsip).

## Quick answers

**Is CVE-2026-40892 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-40892 being exploited in the wild.

**How severe is CVE-2026-40892?** Critical severity, with a CVSS score of 9.8, published 21 April 2026.

**Which products and versions are affected?** PJSIP. The advisory does not name versions.

**Is there a fix for CVE-2026-40892?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**Am I affected by CVE-2026-40892?** Check whether you run 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.

## Affected products

- PJSIP

## Related threats

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- [PJSIP heap buffer overflow in AVI parser](https://junglewise.ai/threats/cve-2026-77396-pjsip-is-a-free-and-open-source-multimedia-communication-library)
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