{"action":"Upgrade katalyst-koi to 4.20.0 or later.","affected":[{"fixed":"4.20.0","introduced":"0"},{"fixed":"5.6.0","introduced":"5.0.0"}],"component":"katalyst-koi","cve_ids":["CVE-2026-44511"],"ecosystem":"RubyGems","epss":0.00197,"exploited":false,"fixed_versions":["4.20.0","5.6.0"],"ghsa_id":"GHSA-4cx3-3c38-j9vv","id":"tcs_01M5KEGKG7VXH795MBT3DQB6C6","modified_at":"2026-05-29T22:00:13.162999427Z","published_at":"2026-05-07T02:13:42Z","references":["https://osv.dev/vulnerability/GHSA-4cx3-3c38-j9vv","https://github.com/katalyst/koi/security/advisories/GHSA-4cx3-3c38-j9vv","https://nvd.nist.gov/vuln/detail/CVE-2026-44511","https://github.com/katalyst/koi","https://github.com/rubysec/ruby-advisory-db/blob/master/gems/katalyst-koi/CVE-2026-44511.yml","https://guides.rubyonrails.org/v5.2.0/security.html#replay-attacks-for-cookiestore-sessions"],"severity":{"label":"high","score":7.4},"sources":[{"source":"osv","source_id":"GHSA-4cx3-3c38-j9vv","url":"https://osv.dev/vulnerability/GHSA-4cx3-3c38-j9vv"}],"summary":"katalyst-koi: Session cookies can be replayed after user logout"}