What’s Vulnerable › Vulnerabilities

CVE-2021-23663: Prototype Pollution

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.2% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2021-12-10 · updated 2026-06-17
• Weakness: CWE-1321

Description

All versions of package sey are vulnerable to Prototype Pollution via the deepmerge() function.

Affected products

• sey: all versions

References

• https://snyk.io/vuln/SNYK-JS-SEY-1727592
• https://snyk.io/vuln/SNYK-JS-SEY-1727592

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