What’s Vulnerable › Vulnerabilities

CVE-2026-16266

• Severity: medium (CVSS 4.0 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.4% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-07-21 · updated 2026-07-23
• Weakness: CWE-1321

Description

Versions of the package mongo-object before 3.0.3 are vulnerable to Prototype Pollution via the expandKey() function in util.js. An attacker can modify the JavaScript prototype chain by supplying a crafted property path containing special keys such as __proto__.

Affected products

• mongo-object: before 3.0.3 — fixed in 3.0.3

How to fix

Upgrade to a fixed version: mongo-object 3.0.3. Check the vendor advisory for mitigations.

References

• https://github.com/longshotlabs/mongo-object/blob/4f7a570f2a2fcfa9417b7870d5f859e9574ec73c/src/util.ts%23L251
• https://github.com/longshotlabs/mongo-object/commit/638314107d8b397e5453c28e41729522b3e8d67c
• https://github.com/longshotlabs/mongo-object/issues/27
• https://security.snyk.io/vuln/SNYK-JS-MONGOOBJECT-13816714
• https://github.com/longshotlabs/mongo-object/issues/27

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