CVE-2021-21332

Cross-site scripting (XSS) vulnerability in the password reset endpoint

Description

Synapse is a Matrix reference homeserver written in python (pypi package matrix-synapse). Matrix is an ecosystem for open federated Instant Messaging and VoIP. In Synapse before version 1.27.0, the password reset endpoint served via Synapse was vulnerable to cross-site scripting (XSS) attacks. The impact depends on the configuration of the domain that Synapse is deployed on, but may allow access to cookies and other browser data, CSRF vulnerabilities, and access to other resources served on the same domain or parent domains. This is fixed in version 1.27.0.

Category

6.9
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.51%
Vendor Advisory fedoraproject.org
Affected: matrix-org synapse
Published at:
Updated at:

References

Link Tags
https://github.com/matrix-org/synapse/security/advisories/GHSA-246w-56m2-5899 third party advisory
https://github.com/matrix-org/synapse/releases/tag/v1.27.0 third party advisory
https://github.com/matrix-org/synapse/pull/9200 third party advisory patch
https://github.com/matrix-org/synapse/commit/e54746bdf7d5c831eabe4dcea76a7626f1de73df third party advisory patch
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TNNAJOZNMVMXM6AS7RFFKB4QLUJ4IFEY/ vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-21332?
CVE-2021-21332 has been scored as a medium severity vulnerability.
How to fix CVE-2021-21332?
To fix CVE-2021-21332, 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-2021-21332 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-21332 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-21332?
CVE-2021-21332 affects matrix-org synapse.
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