Prototype pollution in mongo-object
Priority MEDIUM 61CWE-1321Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- Present
- Impact type
- —
- Confidentiality · integrity · availability
- None · Low · None
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA.
Summary
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__.
Why it matters now
Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00424 36th percentileScored 2026-11-07
Fix Fixed mongo-object: 3.0.3
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | mongo-object | before 3.0.3 | 3.0.3 | Patch available | CNA |
- mongo-object Vendor— Affected before 3.0.3 Fixed in 3.0.3 Patch available CNA
Remediation
- Fix · CNA mongo-object Fixed in 3.0.3
Timeline
- 2026-10-02 Threatist record created from CVE-2026-16266
- 2026-10-03 Alias added: GHSA-c8xx-jpr5-7m25
References
Sources
- CVE-2026-16266 · CVE Program
- CVE-2026-16266 · NVD
- FIRST EPSS
- GHSA-c8xx-jpr5-7m25 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences