{"id":78280,"date":"2026-05-11T22:46:25","date_gmt":"2026-05-11T19:16:25","guid":{"rendered":"https:\/\/afaghhosting.net\/blog\/cve-2026-43969-cookie-request-header-injection-via-unvalidated-encoder-in-cow_cookiecookie-1\/"},"modified":"2026-05-11T22:46:25","modified_gmt":"2026-05-11T19:16:25","slug":"cve-2026-43969-cookie-request-header-injection-via-unvalidated-encoder-in-cow_cookiecookie-1","status":"publish","type":"post","link":"https:\/\/afaghhosting.net\/blog\/cve-2026-43969-cookie-request-header-injection-via-unvalidated-encoder-in-cow_cookiecookie-1\/","title":{"rendered":"CVE-2026-43969 &#8211; Cookie Request Header Injection via Unvalidated Encoder in cow_cookie:cookie\/1"},"content":{"rendered":"<p>CVE ID :CVE-2026-43969<\/p>\n<p>  Published : May 11, 2026, 7:16 p.m. | 43\u00a0minutes ago<\/p>\n<p>  Description :Improper Neutralization of CRLF Sequences (&#8216;CRLF Injection&#8217;) vulnerability in ninenines cowlib allows HTTP request splitting and cookie smuggling via unvalidated cookie name and value fields.<\/p>\n<p>cow_cookie:cookie\/1 in cowlib builds a client-side Cookie: request header from a list of name-value pairs without validating either field. An attacker who controls the cookie names or values passed to this function can inject ;, ,, CR, LF, or TAB characters into the serialized header. This enables two classes of attack: cookie smuggling within a single header (e.g. injecting &#8220;; admin=1&#8221; to introduce a phantom cookie that the receiving server treats as authentic) and HTTP request header splitting (injecting CRLF to append arbitrary headers or smuggle a complete second request against a shared upstream proxy). The decoder side (parse_cookie_name\/1, parse_cookie_value\/1) and setcookie\/3 already validate and reject these characters; the encoder alone is missing the check.<\/p>\n<p>This issue affects cowlib from 2.9.0.<\/p>\n<p>  Severity: 2.1 | LOW<\/p>\n<p>  Visit the link for more details, such as CVSS details, affected products, timeline, and more&#8230;\u00a0<\/p>\n","protected":false},"excerpt":{"rendered":"<p>CVE ID :CVE-2026-43969 Published : May 11, 2026, 7:16 p.m. | 43\u00a0minutes ago Description :Improper Neutralization of CRLF Sequences (&#8216;CRLF Injection&#8217;) vulnerability in ninenines cowlib allows HTTP request splitting and cookie smuggling via unvalidated cookie name and value fields. cow_cookie:cookie\/1 in cowlib builds a client-side Cookie: request header from a list of name-value pairs without &hellip;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[26],"tags":[],"class_list":["post-78280","post","type-post","status-publish","format-standard","hentry","category-vulnerability"],"_links":{"self":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/posts\/78280","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/comments?post=78280"}],"version-history":[{"count":0,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/posts\/78280\/revisions"}],"wp:attachment":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/media?parent=78280"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/categories?post=78280"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/tags?post=78280"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}