{"id":"CVE-2026-99072","summary":"ipv4: stop route notification sizing when nexthop group shrinks","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nipv4: stop route notification sizing when nexthop group shrinks\n\nCommit 680aea08e78c (\"net: ipv4: Emit notification when fib\nhardware flags are changed\") added an RCU-only fib_nlmsg_size() call\nfor asynchronous hardware flag notifications.\n\nfib_nlmsg_size() checks fib_info_num_path() before each iteration,\nthen fib_info_nhc() independently reloads nh-\u003enh_grp. If\nRTM_NEWNEXTHOP replaces a group with fewer paths between those loads,\nfib_info_nhc() returns NULL and fib_nexthop_nlmsg_size() dereferences\nit.\n\nStop sizing when the indexed path is absent. Nexthop groups are\ndense, so the current snapshot has no later path.","modified":"2026-11-01T02:37:40.943905135Z","published":"2026-10-23T12:23:15.735Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/99xxx/CVE-2026-99072.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/72d9d17092bb37b0717f12042a0817d01a1f9e78"},{"type":"WEB","url":"https://git.kernel.org/stable/c/81f0deb02a5b5477f236bbbaed1149b779a8632b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/96f3fbb8575593657c7e80786dc3251d2fe3931b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ad1c9f1b98c92609e9bb2ae8f05916defc3b0a54"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ad2b3a68b8a7d5d27de88e05674e4adb1ce46d88"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c1f48d1c2d5e9efd904dbbc2f2b3d41543e55c49"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d3daa33c7af92e38f2274bbd2576f58bfbaf89e6"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/99xxx/CVE-2026-99072.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-99072"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"680aea08e78c003292415518ad270bc20f9c80b1"},{"fixed":"96f3fbb8575593657c7e80786dc3251d2fe3931b"},{"fixed":"81f0deb02a5b5477f236bbbaed1149b779a8632b"},{"fixed":"72d9d17092bb37b0717f12042a0817d01a1f9e78"},{"fixed":"ad1c9f1b98c92609e9bb2ae8f05916defc3b0a54"},{"fixed":"c1f48d1c2d5e9efd904dbbc2f2b3d41543e55c49"},{"fixed":"ad2b3a68b8a7d5d27de88e05674e4adb1ce46d88"},{"fixed":"d3daa33c7af92e38f2274bbd2576f58bfbaf89e6"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-99072.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.12.0"},{"fixed":"5.15.224"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.191"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.160"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.113"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.57"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.2.11"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-99072.json"}}],"schema_version":"1.9.2"}