{"id":245360,"date":"2026-05-13T15:29:00","date_gmt":"2026-05-13T19:29:00","guid":{"rendered":"https:\/\/news-you-need.com\/index.php\/2026\/05\/13\/fragnesia-is-yet-another-dirty-frag-style-linux-kernel-exploit\/"},"modified":"2026-05-13T16:10:07","modified_gmt":"2026-05-13T20:10:07","slug":"fragnesia-is-yet-another-dirty-frag-style-linux-kernel-exploit-2","status":"publish","type":"post","link":"https:\/\/news-you-need.com\/index.php\/2026\/05\/13\/fragnesia-is-yet-another-dirty-frag-style-linux-kernel-exploit-2\/","title":{"rendered":"Fragnesia Is Yet Another Dirty Frag Style Linux Kernel Exploit"},"content":{"rendered":"<p><a href=\"https:\/\/linuxiac.com\/fragnesia-is-yet-another-dirty-frag-style-linux-kernel-exploit\/\">Fragnesia Is Yet Another Dirty Frag Style Linux Kernel Exploit<\/a><\/p>\n<p><a href=\"https:\/\/linuxiac.com\/fragnesia-is-yet-another-dirty-frag-style-linux-kernel-exploit\/\">https:\/\/linuxiac.com\/fragnesia-is-yet-another-dirty-frag-style-linux-kernel-exploit\/<\/a><\/p>\n<p>Publish Date: <a href=\"publish_date]\">2026-05-13 15:29:00<\/a><\/p>\n<p>Source Domain: <a href=\"linuxiac.com\">linuxiac.com<\/a><\/p>\n<p>Yes, we\u2019re starting to get used to it, since three critical kernel vulnerabilities were discovered in just two weeks. After the Copy Fail and Dirty Frag exploits, a new local Linux privilege escalation exploit named Fragnesia (CVE-2026-46300) has been published by V12 Security, exposing another page-cache corruption path in the Linux kernel\u2019s networking stack.<\/p>\n<p>William Bowling and the V12 team discovered the exploit, which is distinct from Dirty Frag but falls within the same vulnerability class and affects a similar kernel area. The proof of concept shows that Fragnesia exploits a logic flaw in Linux\u2019s XFRM ESP-in-TCP subsystem to perform arbitrary byte writes into the kernel page cache of read-only files.<\/p>\n<p>The vulnerability arises from how the kernel manages shared socket buffer fragments during TCP receive coalescing. According to a patch posted to the netdev mailing list, skb_try_coalesce() can transfer page-backed fragments between socket buffers and lose the SKBFL_SHARED_FRAG marker.<\/p>\n<p>As a result, ESP input code may incorrectly treat these fragments as safe for in-place decryption, even when they are backed by the page cache.<\/p>\n<p>This behavior enables Fragnesia to corrupt cached file pages without altering the file on disk. The proof of concept targets \/usr\/bin\/su, overwriting part of the binary in memory with a stub that spawns a root shell.<\/p>\n<p>Because the change is limited to the page cache, the on-disk binary remains unchanged, but subsequent executions of su may use the modified cached version until the cache is cleared or the system is rebooted.<\/p>\n<p>According to V12 Security, the exploit does not require a race condition. Instead, it relies on first splicing data from a file into a TCP receive queue, then switching the socket into espintcp ULP mode. The kernel processes the queued file-backed pages as ESP ciphertext, allowing controlled byte changes within the cached file page.<\/p>\n<p>The Fragnesia repository identifies affected systems as&#8230;<\/p>\n<p><a href=\"https:\/\/linuxiac.com\/fragnesia-is-yet-another-dirty-frag-style-linux-kernel-exploit\/\">Source<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Fragnesia Is Yet Another Dirty Frag Style Linux Kernel Exploit https:\/\/linuxiac.com\/fragnesia-is-yet-another-dirty-frag-style-linux-kernel-exploit\/ Publish Date: 2026-05-13 15:29:00&#8230;<\/p>\n","protected":false},"author":1,"featured_media":245361,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"fifu_image_url":"https:\/\/linuxiac.com\/wp-content\/uploads\/2026\/05\/fragnesia-bug.jpg","fifu_image_alt":"","footnotes":""},"categories":[48],"tags":[90,31,89,71,57,27],"class_list":["post-245360","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-linux","tag-cve","tag-exploit","tag-flaw","tag-linux","tag-security","tag-vulnerability"],"_links":{"self":[{"href":"https:\/\/news-you-need.com\/index.php\/wp-json\/wp\/v2\/posts\/245360"}],"collection":[{"href":"https:\/\/news-you-need.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/news-you-need.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/news-you-need.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/news-you-need.com\/index.php\/wp-json\/wp\/v2\/comments?post=245360"}],"version-history":[{"count":1,"href":"https:\/\/news-you-need.com\/index.php\/wp-json\/wp\/v2\/posts\/245360\/revisions"}],"predecessor-version":[{"id":245364,"href":"https:\/\/news-you-need.com\/index.php\/wp-json\/wp\/v2\/posts\/245360\/revisions\/245364"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/news-you-need.com\/index.php\/wp-json\/wp\/v2\/media\/245361"}],"wp:attachment":[{"href":"https:\/\/news-you-need.com\/index.php\/wp-json\/wp\/v2\/media?parent=245360"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/news-you-need.com\/index.php\/wp-json\/wp\/v2\/categories?post=245360"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/news-you-need.com\/index.php\/wp-json\/wp\/v2\/tags?post=245360"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}