CVE-2026-40470
A critical XSS vulnerability affected hackage-server and hackage.haskell.org.
Impact
A critical XSS vulnerability affected hackage-server and hackage.haskell.org. HTML and JavaScript files provided in source packages or via the documentation upload facility were served as-is on the main hackage.haskell.org domain. As a consequence, when a user with latent HTTP credentials browses to the package pages or documentation uploaded by a malicious package maintainer, their session can be hijacked to upload packages or documentation, amend maintainers or other package metadata, or perform any other action the user is authorised to do.
Affected packages
This record carries no package version data, so it cannot be matched against a dependency list automatically. Read the advisory and compare your version by hand.