CVE-2021-43307
CVSS v3
7.5
HIGH
EPSS Score
1.6 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
An exponential ReDoS (Regular Expression Denial of Service) can be triggered in the semver-regex npm package, when an attacker is able to supply arbitrary input to the test() method
Technical details
- Published
- 2022-06-02
Frequently asked questions
What is CVE-2021-43307?
An exponential ReDoS (Regular Expression Denial of Service) can be triggered in the semver-regex npm package, when an attacker is able to supply arbitrary input to the test() method
Is CVE-2021-43307 actively exploited?
Active exploitation of CVE-2021-43307 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-2021-43307?
CVE-2021-43307 has a CVSS v3 base score of 7.5 (HIGH severity).
Is CVE-2021-43307 affecting your environment?
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