{"id":79206,"date":"2026-06-02T20:46:37","date_gmt":"2026-06-02T17:16:37","guid":{"rendered":"https:\/\/afaghhosting.net\/blog\/cve-2026-49943-cz-nic-bird-internet-routing-daemon-stack-based-buffer-overflow\/"},"modified":"2026-06-02T20:46:37","modified_gmt":"2026-06-02T17:16:37","slug":"cve-2026-49943-cz-nic-bird-internet-routing-daemon-stack-based-buffer-overflow","status":"publish","type":"post","link":"https:\/\/afaghhosting.net\/blog\/cve-2026-49943-cz-nic-bird-internet-routing-daemon-stack-based-buffer-overflow\/","title":{"rendered":"CVE-2026-49943 &#8211; CZ.NIC BIRD Internet Routing Daemon Stack-Based Buffer Overflow"},"content":{"rendered":"<p>CVE ID :CVE-2026-49943<\/p>\n<p>  Published : June 2, 2026, 5:16 p.m. | 1\u00a0hour, 16\u00a0minutes ago<\/p>\n<p>  Description :CZ.NIC BIRD Internet Routing Daemon through 2.19.0 contains a stack-based buffer overflow in the BGP AS_PATH mask matching implementation in nest\/a-path.c. The as_path_match() function uses a fixed-size stack array of 2048 + 1 pm_pos entries, while parse_path() expands AS_PATH segments from a received BGP UPDATE without enforcing a corresponding capacity limit. When RFC 8654 BGP Extended Messages are enabled and a BIRD filter evaluates an AS path mask expression such as &#8220;bgp_path ~ [= &#8230; =]&#8221;, an established BGP peer can send a long AS_PATH containing more than 2048 expanded ASNs. This causes parse_path()\/as_path_match() to write beyond the fixed stack buffer, resulting in a crash of the daemon. NOTE: reportedly, the Supplier&#8217;s position is that a fix is not being prioritized because all network operators should already be rejecting routes with unusually long attributes.<\/p>\n<p>  Severity: 6.3 | MEDIUM<\/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-2026-49943 Published : June 2, 2026, 5:16 p.m. | 1\u00a0hour, 16\u00a0minutes ago Description :CZ.NIC BIRD Internet Routing Daemon through 2.19.0 contains a stack-based buffer overflow in the BGP AS_PATH mask matching implementation in nest\/a-path.c. The as_path_match() function uses a fixed-size stack array of 2048 + 1 pm_pos entries, while parse_path() expands AS_PATH segments &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-79206","post","type-post","status-publish","format-standard","hentry","category-vulnerability"],"_links":{"self":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/posts\/79206","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=79206"}],"version-history":[{"count":0,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/posts\/79206\/revisions"}],"wp:attachment":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/media?parent=79206"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/categories?post=79206"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/tags?post=79206"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}