https://vulnerability.circl.lu Contains only the most 10 recent entries. http://www.rssboard.org/rss-specification python-feedgen en Thu, 01 Oct 2026 22:56:44 +0000 https://vulnerability.circl.lu/vuln/cve-2026-80557 <p><strong>Affected:</strong> Linux</p> <p>In the Linux kernel, the following vulnerability has been resolved:</p> <p>libceph: fix OOB read in decode_watchers() via missing bounds check</p> <p>ceph_start_decoding() validates that struct_len bytes remain in the buffer after the encoding header, but accepts struct_len=0 as valid: ceph_decode_need(p, end, 0, bad) always passes. When a malicious or compromised OSD sends an obj_list_watch_response_t reply with struct_len=0, ceph_start_decoding() returns success with p == end, leaving zero bytes guaranteed for subsequent reads.</p> <p>The immediately following ceph_decode_32(p) in decode_watchers() has no preceding bounds check. With p == end this is a 4-byte read past the validated buffer boundary. The garbage value is then passed directly to kzalloc_objs() as the watcher count.</p> <p>The sibling function decode_watcher() already uses the safe variants (ceph_decode_copy_safe, ceph_decode_64_safe, ceph_decode_skip_32) after its own ceph_start_decoding() call. decode_watchers() is the only site that uses the bare variant, confirming an oversight.</p> <p>Fix by replacing ceph_decode_32(p) with ceph_decode_32_safe(p, end, *num_watchers, bad), consistent with the established pattern.</p> <p>Attacker model: a malicious or compromised OSD in a multi-tenant Ceph deployment (e.g. cloud) can trigger this against any kernel client that calls CEPH_OSD_OP_LIST_WATCHERS, without any further privileges beyond OSD session establishment.</p> <p>[ idryomov: trim changelog ]</p> <p><strong>Affected:</strong> Linux</p> <p>In the Linux kernel, the following vulnerability has been resolved:</p> <p>libceph: fix OOB read in decode_watchers() via missing bounds check</p> <p>ceph_start_decoding() validates that struct_len bytes remain in the buffer after the encoding header, but accepts struct_len=0 as valid: ceph_decode_need(p, end, 0, bad) always passes. When a malicious or compromised OSD sends an obj_list_watch_response_t reply with struct_len=0, ceph_start_decoding() returns success with p == end, leaving zero bytes guaranteed for subsequent reads.</p> <p>The immediately following ceph_decode_32(p) in decode_watchers() has no preceding bounds check. With p == end this is a 4-byte read past the validated buffer boundary. The garbage value is then passed directly to kzalloc_objs() as the watcher count.</p> <p>The sibling function decode_watcher() already uses the safe variants (ceph_decode_copy_safe, ceph_decode_64_safe, ceph_decode_skip_32) after its own ceph_start_decoding() call. decode_watchers() is the only site that uses the bare variant, confirming an oversight.</p> <p>Fix by replacing ceph_decode_32(p) with ceph_decode_32_safe(p, end, *num_watchers, bad), consistent with the established pattern.</p> <p>Attacker model: a malicious or compromised OSD in a multi-tenant Ceph deployment (e.g. cloud) can trigger this against any kernel client that calls CEPH_OSD_OP_LIST_WATCHERS, without any further privileges beyond OSD session establishment.</p> <p>[ idryomov: trim changelog ]</p> https://vulnerability.circl.lu/vuln/cve-2026-80557