CVE-2021-23406
CVSS v3
9.8
CRITICAL
EPSS Score
2.9 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
This affects the package pac-resolver before 5.0.0. This can occur when used with untrusted input, due to unsafe PAC file handling. **NOTE:** The fix for this vulnerability is applied in the node-degenerator library, a dependency written by the same maintainer.
Technical details
- Published
- 2021-08-24
Frequently asked questions
What is CVE-2021-23406?
This affects the package pac-resolver before 5.0.0. This can occur when used with untrusted input, due to unsafe PAC file handling. **NOTE:** The fix for this vulnerability is applied in the node-degenerator library, a dependency written by the same maintainer.
Is CVE-2021-23406 actively exploited?
Active exploitation of CVE-2021-23406 has not been confirmed. Its EPSS score was 2.9% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-23406?
CVE-2021-23406 has a CVSS v3 base score of 9.8 (CRITICAL severity).
Is CVE-2021-23406 affecting your environment?
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