{"id":21476,"date":"2026-09-12T04:31:14","date_gmt":"2026-09-11T20:31:14","guid":{"rendered":"https:\/\/www.54iter.cn\/?vuln=cve-2026-89554"},"modified":"2026-09-12T04:31:14","modified_gmt":"2026-09-11T20:31:14","slug":"cve-2026-89554","status":"publish","type":"vuln","link":"https:\/\/www.54iter.cn\/?vuln=cve-2026-89554","title":{"rendered":"CVE-2026-89554 &#8211; In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: fix uninitiali"},"content":{"rendered":"<p>In the Linux kernel, the following vulnerability has been resolved:<\/p>\n<p>mptcp: fix uninitialized local_id in syncookie MP_JOIN reconstruction<\/p>\n<p>mptcp_token_join_cookie_init_state() restores remote_nonce, local_nonce,<br \/>\nbackup, join_id, token and msk from the saved cookie entry when rebuilding<br \/>\nthe request socket for a MP_JOIN 4th-ACK handled under SYN cookies, but it<br \/>\ndoes not restore local_id, even though the SYN path saved it.<br \/>\nsubflow_ulp_clone() then reads that uninitialized field and stores it as<br \/>\nthe joined subflow&#8217;s address-ID. Because the request-sock slab is<br \/>\nSLAB_TYPESAFE_BY_RCU and not zeroed on allocation, the value is the stale<br \/>\nbyte of a previously freed request socket, which an off-path peer can<br \/>\ninfluence by sending concurrent MP_JOIN SYNs. This corrupts the path<br \/>\nmanager&#8217;s id-based subflow bookkeeping for the connection.<\/p>\n<p>Restore subflow_req-&gt;local_id from the cookie entry, as done for the other<br \/>\nfields.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>In the Linux kernel, the following vulnerability has been resolved:<\/p>\n<p>mptcp: fix uninitialized local_id in syncookie MP_JOIN reconstruction<\/p>\n<p>mptcp_token_join_cookie_init_state() restores remote_nonce, <\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-21476","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/21476","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln"}],"about":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/types\/vuln"}],"wp:attachment":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=21476"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=21476"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=21476"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}