dbcve.org
Heap-based Buffer OverflowWeakness · CWE-122

CVE-2025-40906

CRITICAL · 9.8 CVSS v3.1 Published 2025-05-16
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

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
BSON::XS versions 0.8.4 and earlier for Perl includes a bundled libbson 1.1.7, which has several vulnerabilities. Those include CVE-2017-14227, CVE-2018-16790, CVE-2023-0437, CVE-2024-6381, CVE-2024-6383, and CVE-2025-0755. BSON-XS was the official Perl XS implementation of MongoDB's BSON serialization, but this distribution has reached its end of life as of August 13, 2020 and is no longer supported.

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

BSON::XS versions 0.8.4 and earlier for Perl ship with a bundled libbson 1.1.7 library containing multiple embedded vulnerabilities (CVE-2017-14227, CVE-2018-16790, CVE-2023-0437, CVE-2024-6381, CVE-2024-6383, CVE-2025-0755). The bundled library is statically compiled into the module, making these vulnerabilities directly exploitable in any Perl application using BSON::XS.

MitigationSince BSON::XS reached end-of-life in August 2020 and is no longer supported, users must migrate to a maintained BSON library for Perl such as the pure-Perl BSON module from MongoDB or verify that their MongoDB driver has been updated to remove the vulnerable bundled code.

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

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 if BSON::XS is installed
    Run: perl -MBSON::XS -e 'print $BSON::XS::VERSION'
    Affected if If the module is installed and returns a version number, BSON::XS is in use
  2. Verify the BSON::XS version
    Compare the installed version to the affected range (0.8.4 and earlier)
    Affected if If the installed version is 0.8.4 or any earlier version, the vulnerable bundled libbson 1.1.7 is present
  3. Check for libbson presence in BSON::XS
    Inspect the BSON::XS installation directory for bundled libbson files (look for libbson-related files or check BSON::XS compiled-in library references)
    Affected if If bundled libbson files exist within the BSON::XS module directory, the static library is present
  4. Identify applications using BSON::XS
    Search Perl codebases for 'use BSON::XS' or 'require BSON::XS' statements
    Affected if If any Perl application loads BSON::XS, it is using the vulnerable bundled library

If BSON::XS version 0.8.4 or earlier is installed and being used by any Perl application, the environment is affected by the embedded libbson vulnerabilities.

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
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Since BSON::XS reached end-of-life in August 2020 and is no longer supported, users must migrate to a maintained BSON library for Perl such as the pure-Perl BSON module from MongoDB or verify that their MongoDB driver has been updated to remove the vulnerable bundled code.

Recommended fix High confidence
  1. 1. Identify all Perl applications using BSON::XS by searching for 'use BSON::XS' or 'require BSON::XS' in codebase
  2. 2. Replace BSON::XS with the officially supported MongoDB Perl driver (MongoDB) which provides BSON functionality
  3. 3. Update any BSON::XS-specific API calls to use the MongoDB module's BSON encoding/decoding methods
  4. 4. Test application functionality thoroughly after migration
  5. 5. Remove BSON::XS from the system using 'cpanm --uninstall BSON::XS' or by removing from cpanfile
  6. 6. Update dependency management files (cpanfile, Makefile.PL, etc.) to remove BSON::XS dependency
Caveat Migration to MongoDB Perl driver requires code changes as BSON::XS API is not compatible

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

Have this fixed Scoped from the published advisory
  • Consultation4.0 h
  • Implementation16.0 h
  • Testing8.0 h
  • Review / QA4.0 h
32.0 hours of engineering $5,600
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $8,960.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2025-40906 — 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-2025-40906 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