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vulnerability

Alpine Linux: CVE-2020-26891: Cross-site Scripting

Severity
4
CVSS
(AV:N/AC:M/Au:N/C:N/I:P/A:N)
Published
Oct 19, 2020
Added
Aug 22, 2024
Modified
Jun 18, 2026

Description

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.

Solution

alpine-linux-upgrade-synapse
Title
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