{"id":"AZL-109196","summary":"CVE-2026-98525 affecting package kernel 6.6.157.1-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nmctp: route: iterate socket tag list in mctp_lookup_prealloc_tag()\n\nWhen a socket transmits a packet with MCTP_TAG_PREALLOC set,\nmctp_lookup_prealloc_tag() iterates over the per-netns &mns-\u003ekeys list\nand matches netid, req_tag, peer_addr, and manual_alloc, without\nchecking whether tmp-\u003esk == &msk-\u003esk. This allows any MCTP socket in the\nsame network namespace to use and consume another socket's preallocated\ntag.\n\nIterate the socket's own tag list (&msk-\u003ekeys via sklist) instead of the\nnamespace-wide &mns-\u003ekeys list in mctp_lookup_prealloc_tag(), ensuring\nthat only tags allocated by msk are matched.\n\nTested in QEMU against Linux 7.3.0-rc3 by allocating a manual tag\n(0x18) on socket A via SIOCMCTPALLOCTAG for peer EID 9 and sending a\n4-byte message with MCTP_TAG_PREALLOC from socket B in the same network\nnamespace. On the unfixed kernel, sendto(sock_b) using socket A's\npreallocated tag succeeds (ret = 4); with this patch applied,\nsendto(sock_b) fails with -ENOENT (errno = 2) while sendto(sock_a)\nsucceeds (ret = 4).","modified":"2026-10-19T14:17:05.745292648Z","published":"2026-10-18T16:17:03Z","upstream":["CVE-2026-98525"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98525"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"6.6.157.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-109196.json"}}],"schema_version":"1.9.0"}