Buffer overflow in Pjsip Pjproject
CVE-2026-40892
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.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.004 (36.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 36th percentile — 36.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.006 · newest: 0.004 · change: -0.002
Affected products
- Pjsip Pjproject — versions <= 2.16
- Pjsip
Weakness classification (CWE)
References
- github.com/pjsip/pjproject/security/advisories/GHSA-2wcg-w3c4-48r7 (Patch, Mitigation, Vendor Advisory)
- github.com/pjsip/pjproject/commit/c82123ea6f3c3652bbc9ebd5e9e658c301451687 (Patch)
Frequently asked questions
- What is CVE-2026-40892?
- CVE-2026-40892 is a critical-severity vulnerability in Pjsip Pjproject, classified under Stack-based Buffer Overflow. CVSS score: 9.8/10. Published 2026-04-21.
- How severe is CVE-2026-40892?
- Critical severity. CVSS v3 base score is 9.8 out of 10.