Vulnerability in Immer Project

CVE-2021-23436

This affects the package immer before 9.0.6. A type confusion vulnerability can lead to a bypass of CVE-2020-28477 when the user-provided keys used in the path parameter are arrays. In particular, this bypass is possible because the condition (p === "__proto__" || p === "constructor") in applyPatches_ returns false if p is ['__proto__'] (or ['constructor']). The === operator (strict equality operator) returns false if the operands have different type.

EPSS: 0.018 (76.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.6 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-23436?
CVE-2021-23436 is a medium-severity vulnerability in Immer Project, classified under Access of Resource Using Incompatible Type (Type Confusion). CVSS score: 5.6/10. Published 2021-09-01.
How severe is CVE-2021-23436?
Medium severity. CVSS v3 base score is 5.6 out of 10.
Is CVE-2021-23436 known to be exploited?
21 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.