CVE-2021-3757
CVSS v3
9.8
CRITICAL
EPSS Score
1.7 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
immer is vulnerable to Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')
Technical details
- Published
- 2021-09-02
Frequently asked questions
What is CVE-2021-3757?
immer is vulnerable to Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')
Is CVE-2021-3757 actively exploited?
Active exploitation of CVE-2021-3757 has not been confirmed. Its EPSS score was 1.7% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-3757?
CVE-2021-3757 has a CVSS v3 base score of 9.8 (CRITICAL severity).
Is CVE-2021-3757 affecting your environment?
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