{"id":"CVE-2026-99073","title":"ipv4: stop exception dump when nexthop group shrinks","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nipv4: stop exception dump when nexthop group shrinks\n\nCommit 4ce5dc9316de (\"inet: switch inet_dump_fib() to RCU\nprotection\") allowed IPv4 FIB dumps to run concurrently …","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 4ce5dc9316de50e0da84beafe55d1344f829cece < f91e472821e32f58b03eb631e20a67157e2b928b","Linux >= 4ce5dc9316de50e0da84beafe55d1344f829cece < 21cba134c30c17ae55f468b5809336437df5d7e6","Linux >= 4ce5dc9316de50e0da84beafe55d1344f829cece < b9a30bb7b831e8c5a47fadbdf1760918aaf009cc","Linux >= 4ce5dc9316de50e0da84beafe55d1344f829cece < 4f4afc07dcb2edd4f9afa36595373f8cdb9b58c2","Linux 6.9"],"published":"2026-10-23","updated":"2026-10-23","sourceUpdated":"2026-10-23T12:23:16.935Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-99073","references":[{"url":"https://git.kernel.org/stable/c/f91e472821e32f58b03eb631e20a67157e2b928b"},{"url":"https://git.kernel.org/stable/c/21cba134c30c17ae55f468b5809336437df5d7e6"},{"url":"https://git.kernel.org/stable/c/b9a30bb7b831e8c5a47fadbdf1760918aaf009cc"},{"url":"https://git.kernel.org/stable/c/4f4afc07dcb2edd4f9afa36595373f8cdb9b58c2"}],"tags":["cve.org"],"ingestedAt":"2026-10-23T13:24:55.515Z","slug":"CVE-2026-99073","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nipv4: stop exception dump when nexthop group shrinks\n\nCommit 4ce5dc9316de (\"inet: switch inet_dump_fib() to RCU\nprotection\") allowed IPv4 FIB dumps to run concurrently with nexthop\nreplacement.\n\nfib_dump_info_fnhe() uses fib_info_num_path() as the loop bound,\nthen fib_info_nhc() independently reloads nh->nh_grp. If\nRTM_NEWNEXTHOP replaces a group with fewer paths between those loads,\nfib_info_nhc() returns NULL and the dump dereferences it through\nnhc_flags.\n\nStop the walk when the indexed path is absent. Nexthop groups are\ndense, so the current snapshot has no later path.\n\n## Affected\n\n- `Linux >= 4ce5dc9316de50e0da84beafe55d1344f829cece < f91e472821e32f58b03eb631e20a67157e2b928b`\n- `Linux >= 4ce5dc9316de50e0da84beafe55d1344f829cece < 21cba134c30c17ae55f468b5809336437df5d7e6`\n- `Linux >= 4ce5dc9316de50e0da84beafe55d1344f829cece < b9a30bb7b831e8c5a47fadbdf1760918aaf009cc`\n- `Linux >= 4ce5dc9316de50e0da84beafe55d1344f829cece < 4f4afc07dcb2edd4f9afa36595373f8cdb9b58c2`\n- `Linux 6.9`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}