{"id":58978,"date":"2026-06-01T14:56:20","date_gmt":"2026-06-01T14:56:20","guid":{"rendered":"https:\/\/zero.redgem.net\/?p=58978"},"modified":"2026-06-01T14:56:20","modified_gmt":"2026-06-01T14:56:20","slug":"nextcloud-open-redirect-in-useroidc-login-flow-via-protocol-relative-url-bypass","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=58978","title":{"rendered":"Nextcloud: Open Redirect in user_oidc login flow via protocol-relative URL bypass_CVE-2026-45278"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Nextcloud is an open source content collaboration platform. From version 6.1.0 to before version 8.2.2, an attacker can craft links that would redirect users to another website, when the victim uses the attackers link to log in via user OIDC. 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From version 6.1.0 to before version 8.2.2, an attacker can craft links that would redirect users to&#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":[6,8,121,12,71,13,7,11,5],"class_list":["post-58978","post","type-post","status-publish","format-standard","hentry","category-category_cve","tag-cve","tag-cvss","tag-cvss-33","tag-exploit","tag-low","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>Nextcloud: Open Redirect in user_oidc login flow via protocol-relative URL bypass_CVE-2026-45278 - 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=58978\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Nextcloud: Open Redirect in user_oidc login flow via protocol-relative URL bypass_CVE-2026-45278 - zero redgem\" \/>\n<meta property=\"og:description\" content=\"{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Nextcloud is an open source content collaboration platform. 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