{"id":55516,"date":"2026-05-19T08:17:45","date_gmt":"2026-05-19T08:17:45","guid":{"rendered":"https:\/\/zero.redgem.net\/?p=55516"},"modified":"2026-05-19T08:17:45","modified_gmt":"2026-05-19T08:17:45","slug":"keycloak-keycloak-access-token-disclosure-and-implicit-flow-bypass-via-forged-client-data","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=55516","title":{"rendered":"Keycloak: keycloak: access token disclosure and implicit flow bypass via forged client data_CVE-2026-7571"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;A flaw was found in Keycloak. A low-privilege user, with knowledge of user credentials and client ID, can bypass a security control intended to disable the implicit flow in OpenID Connect (OIDC) clients. By manipulating client data during a session restart, an attacker can obtain an access token that should not be available. 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A low-privilege user, with knowledge of user credentials and client ID, can bypass a security control intended to disable&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[6,8,50,12,15,13,7,11,5],"class_list":["post-55516","post","type-post","status-publish","format-standard","hentry","category-category_cve","tag-cve","tag-cvss","tag-cvss-71","tag-exploit","tag-high","tag-news","tag-security","tag-tapic","tag-vulnerability"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.5 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Keycloak: keycloak: access token disclosure and implicit flow bypass via forged client data_CVE-2026-7571 - zero redgem<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/zero.redgem.net\/?p=55516\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Keycloak: keycloak: access token disclosure and implicit flow bypass via forged client data_CVE-2026-7571 - zero redgem\" \/>\n<meta property=\"og:description\" content=\"{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;A flaw was found in Keycloak. 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