dbcve.org
PjsipApplication

CVE-2026-40892

CRITICAL · 9.8 CVSS v3.1 Published 2026-04-21
Fix available
A fix is available. Upgrade to 2.17 or later.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click Patch available

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

A stack buffer overflow exists in PJSIP versions 2.16 and earlier in the pjsip_auth_create_digest2() function. When using pre-computed digest credentials (PJSIP_CRED_DATA_DIGEST), the function copies credential data using cred_info->data.slen as the length parameter without validating it against the 128-byte ha1 stack buffer, allowing an attacker to overflow the buffer if data.slen exceeds the expected digest string length.

MitigationUpdate PJSIP to a version newer than 2.16 when available, or implement bounds checking to ensure cred_info->data.slen does not exceed the 128-byte ha1 buffer size before copying credential data.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
PjsipApplication
Affected:< 2.17

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Check installed PJSIP library version
    Run 'pkg-config --modversion libpjproject' or check the pjsip.h header file for PJ_VERSION or PJ_VERSION_STR macros. On Linux: 'grep -r "PJ_VERSION" /usr/include/pjsip*' or check the shared library: 'ldd -l libpjproject.so 2>/dev/null || objdump -T libpjproject.so | grep PJ'
    Affected if Version is 2.16 or earlier (versions prior to 2.17)
  2. Identify if PJSIP_CRED_DATA_DIGEST credential type is in use
    Search source code for 'PJSIP_CRED_DATA_DIGEST' or examine SIP configuration files for credential data that represents pre-computed HA1 digests. Use: 'grep -r "PJSIP_CRED_DATA_DIGEST" /path/to/application/code/'
    Affected if Application code or configuration uses PJSIP_CRED_DATA_DIGEST for credential authentication
  3. Verify credential data length in configuration or code
    If PJSIP_CRED_DATA_DIGEST credentials are found, inspect the credential data length. The MD5 digest string should be exactly 32 hex characters. Check if any credential entry has data.slen exceeding 32 bytes or if custom credential structures exist that set data.slen to values larger than 128
    Affected if Any credential entry has data.slen value greater than 128 or the digest string length exceeds 32 hex characters, indicating potential buffer overflow condition

You are affected if PJSIP version is 2.16 or earlier AND your application uses pre-computed digest credentials (PJSIP_CRED_DATA_DIGEST) with credential data length exceeding the 128-byte ha1 buffer allocation.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 2.17 or later
Fixed in 2.17
Vendor patch github.com →
Interim mitigation

Update PJSIP to a version newer than 2.16 when available, or implement bounds checking to ensure cred_info->data.slen does not exceed the 128-byte ha1 buffer size before copying credential data.

Recommended fix High confidence

2.17

  1. 1. Identify all applications and systems that depend on PJSIP/pjproject library
  2. 2. Backup current pjproject installation and configuration files
  3. 3. Download pjproject version 2.17 or later from the official repository: https://github.com/pjsip/pjproject/releases
  4. 4. If using a package manager (e.g., apt, yum, brew), upgrade to the new version: 'apt-get update && apt-get upgrade pjproject' or equivalent for your package manager
  5. 5. If building from source, run './configure', 'make', 'make install' with the new 2.17 source code
  6. 6. Restart any services or applications that use PJSIP to load the updated library
  7. 7. Verify the upgrade was successful by checking the installed pjproject version
  8. 8. Test that authentication functionality with pre-computed digest credentials (PJSIP_CRED_DATA_DIGEST) still works correctly

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Pjsip Scoped from the published advisory
  • Consultation2.0 h
  • Implementation2.0 h
  • Testing4.0 h
  • Review / QA2.0 h
10.0 hours of engineering $1,720
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,752.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-40892 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-40892 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data