CVE-2018-8899

Name: CVE-2018-8899
Creator: NVD / NIST
Published: 2018-03-22T05:29:00.287+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

UnknownEPSS 1.26%

Last modified Jun 17, 2026

CVE-2018-8899 is a vulnerability of currently unknown severity. 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.. EPSS estimates a 1.26% chance of exploitation in the next 30 days.

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.

Metrics

EPSS Probability

1.26%

65.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-79

Affected Software

Vendor	Product	Versions
Identityserver	Identityserver4	>= 1.0.0, <= 1.5.2
Identityserver	Identityserver4	>= 2.0.0, <= 2.1.2

References

https://github.com/IdentityServer/IdentityServer4/commit/21d0da227f50ac102de469a13bc5a15d2cc0f895Patch, Third Party Advisory
https://github.com/IdentityServer/IdentityServer4/issues/2164Issue Tracking, Third Party Advisory
https://github.com/IdentityServer/IdentityServer4/releases/tag/1.5.3Third Party Advisory
https://github.com/IdentityServer/IdentityServer4/releases/tag/2.1.3Third Party Advisory
https://github.com/IdentityServer/IdentityServer4/commit/21d0da227f50ac102de469a13bc5a15d2cc0f895Patch, Third Party Advisory
https://github.com/IdentityServer/IdentityServer4/issues/2164Issue Tracking, Third Party Advisory
https://github.com/IdentityServer/IdentityServer4/releases/tag/1.5.3Third Party Advisory
https://github.com/IdentityServer/IdentityServer4/releases/tag/2.1.3Third Party Advisory

Timeline

Published: Mar 22, 2018
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2018-8899?

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.

How severe is CVE-2018-8899?

Severity scoring for CVE-2018-8899 is pending analysis. The EPSS model estimates a 1.26% probability of exploitation in the next 30 days.

How do I fix CVE-2018-8899?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2018-8899?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST