{"id":64819,"date":"2026-06-22T12:58:26","date_gmt":"2026-06-22T12:58:26","guid":{"rendered":"https:\/\/zero.redgem.net\/?p=64819"},"modified":"2026-06-22T12:58:26","modified_gmt":"2026-06-22T12:58:26","slug":"aiohttp-tls-server-hostname-override-is-ignored-when-reusing-https-connections","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=64819","title":{"rendered":"AIOHTTP: TLS Server Hostname Override Is Ignored When Reusing HTTPS Connections_CVE-2026-54275"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;AIOHTTP is an asynchronous HTTP client\/server framework for asyncio and Python. Prior to 3.14.1, the server_hostname TLS SNI check can be bypassed when an existing connection is reused. If an application makes multiple requests to the same domain, but with different per-request server_hostname parameters, then the later calls may succeed by reusing the existing connection when they should have been rejected due to the TLS SNI check. 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Prior to 3.14.1, the server_hostname TLS SNI check can be bypassed when an existing&#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":[6,8,150,12,71,13,7,11,5],"class_list":["post-64819","post","type-post","status-publish","format-standard","hentry","category-category_cve","tag-cve","tag-cvss","tag-cvss-27","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>AIOHTTP: TLS Server Hostname Override Is Ignored When Reusing HTTPS Connections_CVE-2026-54275 - 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=64819\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"AIOHTTP: TLS Server Hostname Override Is Ignored When Reusing HTTPS Connections_CVE-2026-54275 - zero redgem\" \/>\n<meta property=\"og:description\" content=\"{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;AIOHTTP is an asynchronous HTTP client\/server framework for asyncio and Python. 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