{"id":42186,"date":"2026-04-12T01:56:11","date_gmt":"2026-04-12T01:56:11","guid":{"rendered":"http:\/\/localhost\/?p=42186"},"modified":"2026-04-12T01:56:11","modified_gmt":"2026-04-12T01:56:11","slug":"optimole-422-unauthenticated-stored-cross-site-scripting-via-srcset-descriptor-parameter","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=42186","title":{"rendered":"Optimole <= 4.2.2 - Unauthenticated Stored Cross-Site Scripting via Srcset Descriptor Parameter_CVE-2026-5217"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;The Optimole \u2013 Optimize Images | Convert WebP \\u0026 AVIF | CDN \\u0026 Lazy Load | Image Optimization plugin for WordPress is vulnerable to Stored Cross-Site Scripting in all versions up to, and including, 4.2.2. This is due to insufficient input sanitization and output escaping on the user-supplied &#8216;s&#8217; parameter (srcset descriptor) in the unauthenticated \/wp-json\/optimole\/v1\/optimizations REST endpoint. The endpoint validates requests using an HMAC signature and timestamp, but these values are exposed directly in the frontend HTML making them accessible to any visitor. The plugin uses sanitize_text_field() on the descriptor value of rest.php, which strips HTML tags but does not escape double quotes. The poisoned descriptor is then stored via transients (backed by the WordPress options table) and later retrieved and injected verbatim into the srcset attribute of tag_replacer.php without proper escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts into pages that will execute whenever a user accesses the injected page.&#8221;,&#8221;published&#8221;:&#8221;2026-04-11T01:24:58.602Z&#8221;,&#8221;modified&#8221;:&#8221;2026-04-11T01:24:58.602Z&#8221;,&#8221;type&#8221;:&#8221;cve&#8221;,&#8221;title&#8221;:&#8221;Optimole \\u003c= 4.2.2 &#8211; Unauthenticated Stored Cross-Site Scripting via Srcset Descriptor Parameter&#8221;,&#8221;source&#8221;:&#8221;Wordfence&#8221;,&#8221;references&#8221;:&#8221;https:\/\/www.wordfence.com\/threat-intel\/vulnerabilities\/id\/50417068-339a-4ae5-9c90-8f08f54ce0af?source=cve\\nhttps:\/\/plugins.trac.wordpress.org\/browser\/optimole-wp\/trunk\/inc\/rest.php#L159\\nhttps:\/\/plugins.trac.wordpress.org\/browser\/optimole-wp\/trunk\/inc\/rest.php#L1008\\nhttps:\/\/plugins.trac.wordpress.org\/browser\/optimole-wp\/trunk\/inc\/tag_replacer.php#L526\\nhttps:\/\/plugins.trac.wordpress.org\/browser\/optimole-wp\/tags\/4.2.1\/inc\/tag_replacer.php#L526\\nhttps:\/\/plugins.trac.wordpress.org\/browser\/optimole-wp\/tags\/4.2.1\/inc\/rest.php#L1008\\nhttps:\/\/plugins.trac.wordpress.org\/browser\/optimole-wp\/tags\/4.2.1\/inc\/rest.php#L159&#8243;,&#8221;id&#8221;:&#8221;CVE-2026-5217&#8243;,&#8221;bulletinFamily&#8221;:&#8221;&#8221;,&#8221;cwe&#8221;:[&#8220;CWE-79&#8243;],&#8221;cvelist&#8221;:null,&#8221;sourceData&#8221;:&#8221;optimole Optimole \u2013 Optimize Images in Real Time 0&#8243;,&#8221;sourceHref&#8221;:&#8221;&#8221;,&#8221;cvss&#8221;:{&#8220;score&#8221;:7.2,&#8221;severity&#8221;:&#8221;HIGH&#8221;,&#8221;vector&#8221;:&#8221;CVSS:3.1\/AV:N\/AC:L\/PR:N\/UI:N\/S:C\/C:L\/I:L\/A:N&#8221;,&#8221;version&#8221;:&#8221;3.1&#8243;},&#8221;cvss2&#8243;:{},&#8221;cvss3&#8243;:{&#8220;version&#8221;:&#8221;&#8221;,&#8221;vectorString&#8221;:&#8221;&#8221;,&#8221;baseScore&#8221;:0,&#8221;baseSeverity&#8221;:&#8221;&#8221;,&#8221;attackVector&#8221;:&#8221;&#8221;,&#8221;attackComplexity&#8221;:&#8221;&#8221;,&#8221;privilegesRequired&#8221;:&#8221;&#8221;,&#8221;userInteraction&#8221;:&#8221;&#8221;,&#8221;scope&#8221;:&#8221;&#8221;,&#8221;confidentialityImpact&#8221;:&#8221;&#8221;,&#8221;integrityImpact&#8221;:&#8221;&#8221;,&#8221;availabilityImpact&#8221;:&#8221;&#8221;,&#8221;cvssV3&#8243;:{&#8220;version&#8221;:&#8221;&#8221;,&#8221;vectorString&#8221;:&#8221;&#8221;,&#8221;baseScore&#8221;:0,&#8221;baseSeverity&#8221;:&#8221;&#8221;,&#8221;attackVector&#8221;:&#8221;&#8221;,&#8221;attackComplexity&#8221;:&#8221;&#8221;,&#8221;privilegesRequired&#8221;:&#8221;&#8221;,&#8221;userInteraction&#8221;:&#8221;&#8221;,&#8221;scope&#8221;:&#8221;&#8221;,&#8221;confidentialityImpact&#8221;:&#8221;&#8221;,&#8221;integrityImpact&#8221;:&#8221;&#8221;,&#8221;availabilityImpact&#8221;:&#8221;&#8221;}},&#8221;href&#8221;:&#8221;&#8221;,&#8221;category_name&#8221;:&#8221;CVE&#8221;,&#8221;post_link&#8221;:&#8221;&#8221;,&#8221;product&#8221;:&#8221;Optimole \u2013 Optimize Images in Real Time&#8221;,&#8221;version&#8221;:&#8221;0&#8243;,&#8221;vendor&#8221;:&#8221;optimole&#8221;,&#8221;ai_description&#8221;:&#8221;&#8221;,&#8221;ai_severity&#8221;:&#8221;&#8221;,&#8221;ai_vendor&#8221;:&#8221;&#8221;,&#8221;ai_product&#8221;:&#8221;&#8221;,&#8221;ai_version&#8221;:&#8221;&#8221;,&#8221;ai_score&#8221;:0}<\/p>\n","protected":false},"excerpt":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;The Optimole \u2013 Optimize Images | Convert WebP \\u0026 AVIF | CDN \\u0026 Lazy Load | Image Optimization plugin for WordPress is vulnerable to Stored&#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":[6,8,39,12,15,13,7,11,5],"class_list":["post-42186","post","type-post","status-publish","format-standard","hentry","category-category_cve","tag-cve","tag-cvss","tag-cvss-72","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>Optimole<\/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=42186\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Optimole\" \/>\n<meta property=\"og:description\" content=\"{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;The Optimole \u2013 Optimize Images | Convert WebP u0026 AVIF | CDN u0026 Lazy Load | Image Optimization plugin for WordPress is vulnerable to Stored...\" \/>\n<meta property=\"og:url\" content=\"https:\/\/zero.redgem.net\/?p=42186\" \/>\n<meta property=\"og:site_name\" content=\"zero redgem\" \/>\n<meta property=\"article:published_time\" content=\"2026-04-12T01:56:11+00:00\" \/>\n<meta name=\"author\" content=\"invoker\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"invoker\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"2 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/?p=42186#article\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/?p=42186\"},\"author\":{\"name\":\"invoker\",\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/#\\\/schema\\\/person\\\/fbfeae8dfad117ac08a7621bee1a1dca\"},\"headline\":\"Optimole\",\"datePublished\":\"2026-04-12T01:56:11+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/?p=42186\"},\"wordCount\":1,\"commentCount\":0,\"publisher\":{\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/#organization\"},\"keywords\":[\"CVE\",\"CVSS\",\"CVSS-7.2\",\"exploit\",\"HIGH\",\"news\",\"Security\",\"tapic\",\"Vulnerability\"],\"articleSection\":[\"category_cve\"],\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"CommentAction\",\"name\":\"Comment\",\"target\":[\"https:\\\/\\\/zero.redgem.net\\\/?p=42186#respond\"]}]},{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/?p=42186\",\"url\":\"https:\\\/\\\/zero.redgem.net\\\/?p=42186\",\"name\":\"Optimole\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/#website\"},\"datePublished\":\"2026-04-12T01:56:11+00:00\",\"breadcrumb\":{\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/?p=42186#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\\\/\\\/zero.redgem.net\\\/?p=42186\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/?p=42186#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\\\/\\\/zero.redgem.net\\\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Optimole\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/#website\",\"url\":\"https:\\\/\\\/zero.redgem.net\\\/\",\"name\":\"zero redgem\",\"description\":\"\",\"publisher\":{\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/#organization\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\\\/\\\/zero.redgem.net\\\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"en-US\"},{\"@type\":\"Organization\",\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/#organization\",\"name\":\"zero redgem\",\"url\":\"https:\\\/\\\/zero.redgem.net\\\/\",\"logo\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/#\\\/schema\\\/logo\\\/image\\\/\",\"url\":\"\",\"contentUrl\":\"\",\"width\":191,\"height\":188,\"caption\":\"zero redgem\"},\"image\":{\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/#\\\/schema\\\/logo\\\/image\\\/\"}},{\"@type\":\"Person\",\"@id\":\"https:\\\/\\\/zero.redgem.net\\\/#\\\/schema\\\/person\\\/fbfeae8dfad117ac08a7621bee1a1dca\",\"name\":\"invoker\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/f17c01d7338e6932bcde121cf83569393df3374625d25afd62677cfb528f2e3e?s=96&d=mm&r=g\",\"url\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/f17c01d7338e6932bcde121cf83569393df3374625d25afd62677cfb528f2e3e?s=96&d=mm&r=g\",\"contentUrl\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/f17c01d7338e6932bcde121cf83569393df3374625d25afd62677cfb528f2e3e?s=96&d=mm&r=g\",\"caption\":\"invoker\"},\"sameAs\":[\"https:\\\/\\\/zero.redgem.net\"],\"url\":\"https:\\\/\\\/zero.redgem.net\\\/?author=1\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Optimole","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/zero.redgem.net\/?p=42186","og_locale":"en_US","og_type":"article","og_title":"Optimole","og_description":"{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;The Optimole \u2013 Optimize Images | Convert WebP u0026 AVIF | CDN u0026 Lazy Load | Image Optimization plugin for WordPress is vulnerable to Stored...","og_url":"https:\/\/zero.redgem.net\/?p=42186","og_site_name":"zero redgem","article_published_time":"2026-04-12T01:56:11+00:00","author":"invoker","twitter_card":"summary_large_image","twitter_misc":{"Written by":"invoker","Est. reading time":"2 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/zero.redgem.net\/?p=42186#article","isPartOf":{"@id":"https:\/\/zero.redgem.net\/?p=42186"},"author":{"name":"invoker","@id":"https:\/\/zero.redgem.net\/#\/schema\/person\/fbfeae8dfad117ac08a7621bee1a1dca"},"headline":"Optimole","datePublished":"2026-04-12T01:56:11+00:00","mainEntityOfPage":{"@id":"https:\/\/zero.redgem.net\/?p=42186"},"wordCount":1,"commentCount":0,"publisher":{"@id":"https:\/\/zero.redgem.net\/#organization"},"keywords":["CVE","CVSS","CVSS-7.2","exploit","HIGH","news","Security","tapic","Vulnerability"],"articleSection":["category_cve"],"inLanguage":"en-US","potentialAction":[{"@type":"CommentAction","name":"Comment","target":["https:\/\/zero.redgem.net\/?p=42186#respond"]}]},{"@type":"WebPage","@id":"https:\/\/zero.redgem.net\/?p=42186","url":"https:\/\/zero.redgem.net\/?p=42186","name":"Optimole","isPartOf":{"@id":"https:\/\/zero.redgem.net\/#website"},"datePublished":"2026-04-12T01:56:11+00:00","breadcrumb":{"@id":"https:\/\/zero.redgem.net\/?p=42186#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/zero.redgem.net\/?p=42186"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/zero.redgem.net\/?p=42186#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/zero.redgem.net\/"},{"@type":"ListItem","position":2,"name":"Optimole"}]},{"@type":"WebSite","@id":"https:\/\/zero.redgem.net\/#website","url":"https:\/\/zero.redgem.net\/","name":"zero redgem","description":"","publisher":{"@id":"https:\/\/zero.redgem.net\/#organization"},"potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/zero.redgem.net\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-US"},{"@type":"Organization","@id":"https:\/\/zero.redgem.net\/#organization","name":"zero redgem","url":"https:\/\/zero.redgem.net\/","logo":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/zero.redgem.net\/#\/schema\/logo\/image\/","url":"","contentUrl":"","width":191,"height":188,"caption":"zero redgem"},"image":{"@id":"https:\/\/zero.redgem.net\/#\/schema\/logo\/image\/"}},{"@type":"Person","@id":"https:\/\/zero.redgem.net\/#\/schema\/person\/fbfeae8dfad117ac08a7621bee1a1dca","name":"invoker","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/secure.gravatar.com\/avatar\/f17c01d7338e6932bcde121cf83569393df3374625d25afd62677cfb528f2e3e?s=96&d=mm&r=g","url":"https:\/\/secure.gravatar.com\/avatar\/f17c01d7338e6932bcde121cf83569393df3374625d25afd62677cfb528f2e3e?s=96&d=mm&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/f17c01d7338e6932bcde121cf83569393df3374625d25afd62677cfb528f2e3e?s=96&d=mm&r=g","caption":"invoker"},"sameAs":["https:\/\/zero.redgem.net"],"url":"https:\/\/zero.redgem.net\/?author=1"}]}},"_links":{"self":[{"href":"https:\/\/zero.redgem.net\/index.php?rest_route=\/wp\/v2\/posts\/42186","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/zero.redgem.net\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/zero.redgem.net\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/zero.redgem.net\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/zero.redgem.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=42186"}],"version-history":[{"count":0,"href":"https:\/\/zero.redgem.net\/index.php?rest_route=\/wp\/v2\/posts\/42186\/revisions"}],"wp:attachment":[{"href":"https:\/\/zero.redgem.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=42186"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/zero.redgem.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=42186"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/zero.redgem.net\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=42186"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}