CVE-2021-23387

Public Exploit
Open Redirect

Description

The package trailing-slash before 2.0.1 are vulnerable to Open Redirect via the use of trailing double slashes in the URL when accessing the vulnerable endpoint (such as https://example.com//attacker.example/). The vulnerable code is in index.js::createTrailing(), as the web server uses relative URLs instead of absolute URLs.

Category

5.4
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.26%
Third-Party Advisory github.com Third-Party Advisory snyk.io
Affected: n/a trailing-slash
Published at:
Updated at:

References

Link Tags
https://snyk.io/vuln/SNYK-JS-TRAILINGSLASH-1085707 patch third party advisory exploit
https://github.com/fardog/trailing-slash/blob/f640ece055fe85275c983de5eb94661b95e35670/index.js%23L36 broken link
https://github.com/fardog/trailing-slash/commit/f8e66f1429308247e5a119d430203077d8f05048 third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-23387?
CVE-2021-23387 has been scored as a medium severity vulnerability.
How to fix CVE-2021-23387?
To fix CVE-2021-23387, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-23387 being actively exploited in the wild?
It is possible that CVE-2021-23387 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-23387?
CVE-2021-23387 affects n/a trailing-slash.
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