CVE-2021-27736

Public Exploit

Description

FusionAuth fusionauth-samlv2 before 0.5.4 allows XXE attacks via a forged AuthnRequest or LogoutRequest because parseFromBytes uses javax.xml.parsers.DocumentBuilderFactory unsafely.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.28%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory compass-security.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://github.com/FusionAuth/fusionauth-samlv2/compare/0.5.3...0.5.4 third party advisory patch
https://github.com/FusionAuth/fusionauth-samlv2/commit/c66fb689d50010662f705d5b585c6388ce555dbd third party advisory patch
https://www.compass-security.com/fileadmin/Research/Advisories/2021-03_CSNC-2021-004_FusionAuth_SAML_Library_XML_External_Entity.txt third party advisory exploit

Frequently Asked Questions

What is the severity of CVE-2021-27736?
CVE-2021-27736 has been scored as a medium severity vulnerability.
How to fix CVE-2021-27736?
To fix CVE-2021-27736, 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-2021-27736 being actively exploited in the wild?
It is possible that CVE-2021-27736 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.
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