CVE-2021-20085
CVSS v3
8.8
HIGH
EPSS Score
1.6 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') in backbone-query-parameters 0.4.0 allows a malicious user to inject properties into Object.prototype.
Technical details
- Published
- 2021-04-23
Frequently asked questions
What is CVE-2021-20085?
Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') in backbone-query-parameters 0.4.0 allows a malicious user to inject properties into Object.prototype.
Is CVE-2021-20085 actively exploited?
Active exploitation of CVE-2021-20085 has not been confirmed. Its EPSS score was 1.6% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-20085?
CVE-2021-20085 has a CVSS v3 base score of 8.8 (HIGH severity).
Is CVE-2021-20085 affecting your environment?
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