Quick answers
- Is CVE-2026-125117 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-125117 being exploited in the wild.
- How severe is CVE-2026-125117?
- High severity, with a CVSS score of 8.2, published 9 November 2026.
- Which products and versions are affected?
- Automattic Mongoose before 6.13.12, 7.x before 7.8.13, 8.x before 8.24.7, 9.x before 9.11.4; mongoose (npm) < 6.13.12, SEMVER:introduced=0,fixed=6.13.12.
- Is there a fix for CVE-2026-125117?
- Yes. mongoose (npm): upgrade to 6.13.12 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-125117 attacked?
- It is attacked over the network.
- Am I affected by CVE-2026-125117?
- Check whether you run Automattic Mongoose or mongoose (npm) at an affected version. 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.
How to fix
- mongoose (npm): upgrade to 6.13.12 or later
npm install mongoose@6.13.12
Technical details
The vulnerability exists in Mongoose's init(), $__set, and mergeClone functions, which descend into inherited properties when processing database documents without proper filtering of dangerous keys like toString and valueOf. By controlling dotted paths in subdocuments with strict: false, or through findOneAndReplace() replacements and Query.prototype.merge() calls, an attacker can overwrite properties on shared built-in objects such as Object.prototype. This causes Object.prototype.toString to fail for unrelated models and allows alteration of shared validators and schema options.
Affected products
- Automattic Mongoose before 6.13.12, 7.x before 7.8.13, 8.x before 8.24.7, 9.x before 9.11.4
Identifiers
- CVE-2026-125117
- GHSA-8332-j7wj-wjw4
Timeline
- 2026-11-09: disclosed