CVE-2021-27516
CVSS v3
7.5
HIGH
EPSS Score
2.5 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
URI.js (aka urijs) before 1.19.6 mishandles certain uses of backslash such as http:\\/ and interprets the URI as a relative path.
Technical details
- Published
- 2021-02-22
Frequently asked questions
What is CVE-2021-27516?
URI.js (aka urijs) before 1.19.6 mishandles certain uses of backslash such as http:\\/ and interprets the URI as a relative path.
Is CVE-2021-27516 actively exploited?
Active exploitation of CVE-2021-27516 has not been confirmed. Its EPSS score was 2.5% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-27516?
CVE-2021-27516 has a CVSS v3 base score of 7.5 (HIGH severity).
Is CVE-2021-27516 affecting your environment?
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