{"id":245783,"date":"2026-10-22T05:34:01","date_gmt":"2026-10-22T10:34:01","guid":{"rendered":"https:\/\/lifeboat.com\/blog\/2026\/10\/new-qpack-flaws-can-crash-http-3-servers-trigger-up-to-4000-fold-memory-amplification"},"modified":"2026-10-22T05:34:01","modified_gmt":"2026-10-22T10:34:01","slug":"new-qpack-flaws-can-crash-http-3-servers-trigger-up-to-4000-fold-memory-amplification","status":"publish","type":"post","link":"https:\/\/lifeboat.com\/blog\/2026\/10\/new-qpack-flaws-can-crash-http-3-servers-trigger-up-to-4000-fold-memory-amplification","title":{"rendered":"New QPACK Flaws Can Crash HTTP\/3 Servers, Trigger Up to 4,000-Fold Memory Amplification"},"content":{"rendered":"\n<p>A remote attacker who has not logged in can crash many HTTP\/3 web servers with a single connection, security firm FoxIO <a href=\"https:\/\/foxio.io\/blog\/header-accordions-qpack-amplification-attacks-against-http-3-servers\" target=\"_blank\">disclosed<\/a>, releasing working proof-of-concept code.<\/p>\n<p>By sending a small batch of compressed HTTP headers that expands in memory to a much larger set, the attacker can force the server to use thousands of times more memory than it received, enough to run a default server out of memory.<\/p>\n<p>The flaws cause only denial-of-service attacks, with no evidence of data theft or code execution and no public reports of attacks in the wild. Fixes are out for quic-go, Cloudflare quiche, lsquic and Wireshark, but Bun, the h3 Rust library and aioquic were still unpatched at disclosure.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>A remote attacker who has not logged in can crash many HTTP\/3 web servers with a single connection, security firm FoxIO disclosed, releasing working proof-of-concept code. By sending a small batch of compressed HTTP headers that expands in memory to a much larger set, the attacker can force the server to use thousands of times [\u2026]<\/p>\n","protected":false},"author":427,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1492],"tags":[],"class_list":["post-245783","post","type-post","status-publish","format-standard","hentry","category-security"],"_links":{"self":[{"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/posts\/245783","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/users\/427"}],"replies":[{"embeddable":true,"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/comments?post=245783"}],"version-history":[{"count":0,"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/posts\/245783\/revisions"}],"wp:attachment":[{"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/media?parent=245783"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/categories?post=245783"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/tags?post=245783"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}