{"id":42458,"date":"2026-04-12T02:04:30","date_gmt":"2026-04-12T02:04:30","guid":{"rendered":"http:\/\/localhost\/?p=42458"},"modified":"2026-04-12T02:04:30","modified_gmt":"2026-04-12T02:04:30","slug":"integer-underflow-in-x509-san-parsing-in-wolfssl","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=42458","title":{"rendered":"Integer underflow in X.509 SAN parsing in wolfSSL_CVE-2026-5188"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;An integer underflow issue exists in wolfSSL when parsing the Subject Alternative Name (SAN) extension of X.509 certificates. A malformed certificate can specify an entry length larger than the enclosing sequence, causing the internal length counter to wrap during parsing. This results in incorrect handling of certificate data. 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A malformed certificate can specify an entry&#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":[6,8,147,12,71,13,7,11,5],"class_list":["post-42458","post","type-post","status-publish","format-standard","hentry","category-category_cve","tag-cve","tag-cvss","tag-cvss-23","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>Integer underflow in X.509 SAN parsing in wolfSSL_CVE-2026-5188 - 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=42458\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Integer underflow in X.509 SAN parsing in wolfSSL_CVE-2026-5188 - zero redgem\" \/>\n<meta property=\"og:description\" content=\"{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;An integer underflow issue exists in wolfSSL when parsing the Subject Alternative Name (SAN) extension of X.509 certificates. 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