{"schema":"threatline.record/2","record":{"id":"CVE-2026-99201","aliases":[],"summary":"netlink: avoid hashing the network namespace pointer","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetlink: avoid hashing the network namespace pointer\n\nThe netlink rhashtable key includes a raw struct net pointer and a\nuser-controlled port ID. Both /proc/net/netlink and socket diagnostics\nexpose the table's bucket order. By binding and rebinding chosen\nNETLINK_USERSOCK port IDs, an unprivileged reader can distinguish equal\nbuckets and recover the low bits of the Jenkins hash. Its 32-bit seed\nand the limited set of kernel-image slides can then be searched offline\nto recover the address of init_net.\n\nUse the namespace's unique, non-address net_cookie in the comparison\nkey instead. It is assigned before the per-net initializers run and\nremains unchanged for the namespace's lifetime. The lookup key and\nobject hash are still built by netlink_compare_arg_init(), keeping\nlookup, insertion, removal and rehashing consistent while preserving\nnamespace separation. Neither public table walker needs to change.\n\nReading the socket's namespace cookie in netlink_compare() is safe\nunder RCU, including during namespace teardown. netlink_release()\nremoves the socket from the hash table and defers its final put with\ncall_rcu(). cleanup_net() runs the per-net exit methods and waits for\noutstanding RCU callbacks with rcu_barrier() before freeing namespace\nstorage.\n\nUnlike ns.ns_id, net_cookie is also available and initialized during\nsetup_net() in older stable kernels, making the change straightforward\nto backport to v5.15 and later.","categories":["Operating systems"],"product":"Linux","vendor":"Linux","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-99201","source_modified_at":"2026-10-28T10:35:56.069Z","fetched_at":"2026-10-28T15:55:58.673066Z","product":"Linux","vendor":"Linux","versions":[{"version":"c428ecd1a21f1457ca3beb4df71b8a079c410e41","lessThan":"bdd55b8a8acbf6b4840ab420eb6a63774bf4593b","status":"affected","versionType":"git"},{"version":"c428ecd1a21f1457ca3beb4df71b8a079c410e41","lessThan":"078deff25f8a849ecd1c3fe17b1e473b1cf44f28","status":"affected","versionType":"git"},{"version":"c428ecd1a21f1457ca3beb4df71b8a079c410e41","lessThan":"f88bb3606e4bd11ee035b682cddc2999e604609a","status":"affected","versionType":"git"}],"defaultStatus":"unaffected"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-99201","source_modified_at":"2026-10-28T10:35:56.069Z","fetched_at":"2026-10-28T15:55:58.673066Z","product":"Linux","vendor":"Linux","versions":[{"version":"4.1","status":"affected"},{"version":"0","lessThan":"4.1","status":"unaffected","versionType":"semver"},{"version":"6.18.59","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.13","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}],"defaultStatus":"affected"}],"fixed_versions":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-99201","source_modified_at":"2026-10-28T10:35:56.069Z","fetched_at":"2026-10-28T15:55:58.673066Z","package":{"name":"Linux","ecosystem":null},"version":"078deff25f8a849ecd1c3fe17b1e473b1cf44f28","basis":"first unaffected version stated in the CVE record"}],"cvss":null,"severity":null,"kev":{"listed":false},"epss":{"probability":null,"percentile":null,"score_date":null},"published_at":"2026-10-28T10:35:56.069Z","modified_at":"2026-10-28T10:35:56.069Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-99201","fetched_at":"2026-10-28T15:55:58.673066Z","source_modified_at":"2026-10-28T10:35:56.069Z"}],"sources":["CVE List"],"references":[{"source":"CVE List","url":"https://git.kernel.org/stable/c/bdd55b8a8acbf6b4840ab420eb6a63774bf4593b"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/078deff25f8a849ecd1c3fe17b1e473b1cf44f28"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/f88bb3606e4bd11ee035b682cddc2999e604609a"}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":"product","confidence":"heuristic","reviewed":false},"change_timestamp":"2026-10-28T10:35:56.069Z","content_hash":"eecbc287054679e85074c3fcfa768ef62c9243042e14f2854fb439a9e7989213"}}