{"id":21553,"date":"2026-09-12T04:31:20","date_gmt":"2026-09-11T20:31:20","guid":{"rendered":"https:\/\/www.54iter.cn\/?vuln=cve-2026-89631"},"modified":"2026-09-12T04:31:20","modified_gmt":"2026-09-11T20:31:20","slug":"cve-2026-89631","status":"publish","type":"vuln","link":"https:\/\/www.54iter.cn\/?vuln=cve-2026-89631","title":{"rendered":"CVE-2026-89631 &#8211; In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: reject a"},"content":{"rendered":"<p>In the Linux kernel, the following vulnerability has been resolved:<\/p>\n<p>smb: client: reject a tree connect response whose byte count is too small<\/p>\n<p>CIFSTCon() bounds its strnlen() over the byte area with the server&#8217;s<br \/>\nByteCount minus two, which for ByteCount 0 or 1 goes negative as an int<br \/>\nand converts to a huge size_t.  The later subtraction wraps the __u16<br \/>\nbytes_left, and that is what bounds cifs_strndup_from_utf16(): a bound of<br \/>\nup to 65535 against a ~16 KB cifs_req_poolp object runs off the end of the<br \/>\nslab object, and the bytes reach userspace through tcon-&gt;nativeFileSystem<br \/>\nin \/proc\/fs\/cifs\/DebugData.<\/p>\n<p>Reject a byte area too small for what the parser consumes.  Two bytes is<br \/>\nthe least it can consume, and no conformant response carries fewer.  The<br \/>\nnew trace point is the 129th smb_eio_trace entry, which __mode(byte)<br \/>\ncannot represent, so the attribute goes with it.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>In the Linux kernel, the following vulnerability has been resolved:<\/p>\n<p>smb: client: reject a tree connect response whose byte count is too small<\/p>\n<p>CIFSTCon() bounds its strnlen() over the byte area with <\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-21553","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/21553","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=21553"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=21553"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=21553"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}