CVE-2018-8899

Description

IdentityServer IdentityServer4 1.x before 1.5.3 and 2.x before 2.1.3 does not encode the redirect URI on the authorization response page, which might lead to XSS in some configurations.

Category

6.1
CVSS
Severity: Medium
CVSS 3.0 •
CVSS 2.0 •
EPSS 0.29%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://github.com/IdentityServer/IdentityServer4/commit/21d0da227f50ac102de469a13bc5a15d2cc0f895 third party advisory patch
https://github.com/IdentityServer/IdentityServer4/releases/tag/2.1.3 third party advisory
https://github.com/IdentityServer/IdentityServer4/issues/2164 issue tracking third party advisory
https://github.com/IdentityServer/IdentityServer4/releases/tag/1.5.3 third party advisory

Frequently Asked Questions

What is the severity of CVE-2018-8899?
CVE-2018-8899 has been scored as a medium severity vulnerability.
How to fix CVE-2018-8899?
To fix CVE-2018-8899, 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-2018-8899 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2018-8899 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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