VDB
CVE-2020-26891
CVE-2020-26891
PUBLISHED
AuthRestServlet in Matrix Synapse before 1.21.0 is vulnerable to XSS due to unsafe interpolation of the session GET parameter. This allows a remote attacker to execute an XSS attack on the domain Synapse is hosted on, by supplying the victim user with a malicious URL to the /_matrix/client/r0/auth/*/fallback/web or /_matrix/client/unstable/auth/*/fallback/web Synapse endpoints.
EPSS 0.44% · 63.5th percentile
Risk Scores
EPSS Score
0.44%
63.5th percentile
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Ubuntu:Pro:18.04:LTS | matrix-synapse | 0, 0.19.2+dfsg-6, 0.24.0+dfsg-1 |
| Ubuntu:Pro:20.04:LTS | matrix-synapse | 1.8.0-1, 1.7.3-1, 1.9.0-1 |
| Ubuntu:Pro:22.04:LTS | matrix-synapse | 1.39.0-1, 1.47.0-2, 1.47.1-1 |
Timeline
- Oct 16, 2020 CVE Published
- Apr 14, 2021 EPSS Score
- Jun 23, 2021 EPSS Score
- Aug 24, 2021 EPSS Score
- Dec 27, 2021 EPSS Score
- Jan 6, 2022 EPSS Score
- Feb 4, 2022 EPSS Score
- Feb 28, 2022 EPSS Score
- Apr 1, 2022 EPSS Score
- Jul 3, 2022 EPSS Score
- Sep 4, 2022 EPSS Score
- Nov 6, 2022 EPSS Score
References
- https://ubuntu.com/security/CVE-2020-26891 third-party-advisory
- https://github.com/matrix-org/synapse/pull/8444 third-party-advisory
- https://github.com/matrix-org/synapse/releases third-party-advisory
- https://matrix.org/blog/2020/10/15/synapse-1-21-2-released-and-security-advisory third-party-advisory
- https://www.cve.org/CVERecord?id=CVE-2020-26891 third-party-advisory