CVE-2021-23558: Prototype Pollution

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.6% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2022-01-28 · updated 2026-06-17
Weakness: CWE-1321

Description

The package bmoor before 0.10.1 are vulnerable to Prototype Pollution due to missing sanitization in set function. **Note:** This vulnerability derives from an incomplete fix in [CVE-2020-7736](https://security.snyk.io/vuln/SNYK-JS-BMOOR-598664)

Affected products

bmoor: before 0.10.1 — fixed in 0.10.1

How to fix

Upgrade to a fixed version: bmoor 0.10.1. Check the vendor advisory for mitigations.

References

https://github.com/b-heilman/bmoor/commit/29b0162cc1dc1791fc060891f568b0ae29bc542b
https://snyk.io/blog/remediate-javascript-type-confusion-bypassed-input-validation/
https://snyk.io/vuln/SNYK-JS-BMOOR-2342622
https://github.com/b-heilman/bmoor/commit/29b0162cc1dc1791fc060891f568b0ae29bc542b
https://snyk.io/blog/remediate-javascript-type-confusion-bypassed-input-validation/
https://snyk.io/vuln/SNYK-JS-BMOOR-2342622

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