{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2022-48785","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2024-06-20T11:09:39.069Z","datePublished":"2024-07-16T11:13:21.118Z","dateUpdated":"2026-08-05T08:52:15.292Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-05T08:52:15.292Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: mcast: use rcu-safe version of ipv6_get_lladdr()\n\nSome time ago 8965779d2c0e (\"ipv6,mcast: always hold idev->lock before mca_lock\")\nswitched ipv6_get_lladdr() to __ipv6_get_lladdr(), which is rcu-unsafe\nversion. That was OK, because idev->lock was held for these codepaths.\n\nIn 88e2ca308094 (\"mld: convert ifmcaddr6 to RCU\") these external locks were\nremoved, so we probably need to restore the original rcu-safe call.\n\nOtherwise, we occasionally get a machine crashed/stalled with the following\nin dmesg:\n\n[ 3405.966610][T230589] general protection fault, probably for non-canonical address 0xdead00000000008c: 0000 [#1] SMP NOPTI\n[ 3405.982083][T230589] CPU: 44 PID: 230589 Comm: kworker/44:3 Tainted: G           O      5.15.19-cloudflare-2022.2.1 #1\n[ 3405.998061][T230589] Hardware name: SUPA-COOL-SERV\n[ 3406.009552][T230589] Workqueue: mld mld_ifc_work\n[ 3406.017224][T230589] RIP: 0010:__ipv6_get_lladdr+0x34/0x60\n[ 3406.025780][T230589] Code: 57 10 48 83 c7 08 48 89 e5 48 39 d7 74 3e 48 8d 82 38 ff ff ff eb 13 48 8b 90 d0 00 00 00 48 8d 82 38 ff ff ff 48 39 d7 74 22 <66> 83 78 32 20 77 1b 75 e4 89 ca 23 50 2c 75 dd 48 8b 50 08 48 8b\n[ 3406.055748][T230589] RSP: 0018:ffff94e4b3fc3d10 EFLAGS: 00010202\n[ 3406.065617][T230589] RAX: dead00000000005a RBX: ffff94e4b3fc3d30 RCX: 0000000000000040\n[ 3406.077477][T230589] RDX: dead000000000122 RSI: ffff94e4b3fc3d30 RDI: ffff8c3a31431008\n[ 3406.089389][T230589] RBP: ffff94e4b3fc3d10 R08: 0000000000000000 R09: 0000000000000000\n[ 3406.101445][T230589] R10: ffff8c3a31430000 R11: 000000000000000b R12: ffff8c2c37887100\n[ 3406.113553][T230589] R13: ffff8c3a39537000 R14: 00000000000005dc R15: ffff8c3a31431000\n[ 3406.125730][T230589] FS:  0000000000000000(0000) GS:ffff8c3b9fc80000(0000) knlGS:0000000000000000\n[ 3406.138992][T230589] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[ 3406.149895][T230589] CR2: 00007f0dfea1db60 CR3: 000000387b5f2000 CR4: 0000000000350ee0\n[ 3406.162421][T230589] Call Trace:\n[ 3406.170235][T230589]  <TASK>\n[ 3406.177736][T230589]  mld_newpack+0xfe/0x1a0\n[ 3406.186686][T230589]  add_grhead+0x87/0xa0\n[ 3406.195498][T230589]  add_grec+0x485/0x4e0\n[ 3406.204310][T230589]  ? newidle_balance+0x126/0x3f0\n[ 3406.214024][T230589]  mld_ifc_work+0x15d/0x450\n[ 3406.223279][T230589]  process_one_work+0x1e6/0x380\n[ 3406.232982][T230589]  worker_thread+0x50/0x3a0\n[ 3406.242371][T230589]  ? rescuer_thread+0x360/0x360\n[ 3406.252175][T230589]  kthread+0x127/0x150\n[ 3406.261197][T230589]  ? set_kthread_struct+0x40/0x40\n[ 3406.271287][T230589]  ret_from_fork+0x22/0x30\n[ 3406.280812][T230589]  </TASK>\n[ 3406.288937][T230589] Modules linked in: ... [last unloaded: kheaders]\n[ 3406.476714][T230589] ---[ end trace 3525a7655f2f3b9e ]---"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","baseScore":8.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:A - Vulnerable mld_newpack()/__ipv6_get_lladdr() runs from mld_gq_work when processing ICMPv6 MLD queries (icmpv6_rcv → igmp6_event_query). MLD requires a link-local source and hop_limit 1, so it is link-scoped (Adjacent), not Internet-routable.\nAC:L - An on-link attacker controls both sides of the race: Router Advertisements (accept_ra/autoconf default on) create short-lived inet6_ifaddr entries whose expiry calls list_del_rcu on addr_list, while concurrent MLD General Queries trigger the unlocked reverse walk in mld_newpack.\nPR:N - MLD query and RA reception perform no authentication or capability checks; any adjacent IPv6 peer can inject these packets on a shared L2 segment.\nUI:N - The kernel automatically queues and processes MLD queries and applies RA prefix lifetimes without any victim interactive action such as mounting or opening a file.\nS:U - Impact is confined to in-kernel IPv6 address-list/heap state on the local host (standard kernel memory corruption), with no VM escape or other cross-authority boundary crossed.\nC:H - This is a use-after-free on inet6_ifaddr: __ipv6_get_lladdr walks addr_list without idev->lock or rcu_read_lock while ipv6_del_addr does list_del_rcu/kfree_rcu, enabling reuse of the freed object for arbitrary kernel reads.\nI:H - The same UAF on a list-linked inet6_ifaddr allows heap spraying and corrupted list/pointer writes (list_del_rcu poisons prev used by the reverse walk), supporting arbitrary write and control-flow hijacking under standard UAF exploitation.\nA:H - The bug manifests as a general protection fault on LIST_POISON in __ipv6_get_lladdr (as in the Cloudflare crash on mld_ifc_work), i.e. a kernel oops/panic that an adjacent peer can re-trigger."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/net/addrconf.h","net/ipv6/addrconf.c","net/ipv6/mcast.c"],"versions":[{"version":"676457fe5ad19517a8b21d1c3f4d23512118f6a3","lessThan":"c49c69dc9f3e699fa3150aca7b189eea707b4047","status":"affected","versionType":"git"},{"version":"88e2ca3080947fe22eb520c1f8231e79a105d011","lessThan":"3e11ef1903cf6c2fba35594b193a3570854d9e9e","status":"affected","versionType":"git"},{"version":"88e2ca3080947fe22eb520c1f8231e79a105d011","lessThan":"27f567c84f446048670376827e356f9c92033bf9","status":"affected","versionType":"git"},{"version":"88e2ca3080947fe22eb520c1f8231e79a105d011","lessThan":"26394fc118d6115390bd5b3a0fb17096271da227","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/net/addrconf.h","net/ipv6/addrconf.c","net/ipv6/mcast.c"],"versions":[{"version":"5.13","status":"affected"},{"version":"0","lessThan":"5.13","status":"unaffected","versionType":"semver"},{"version":"5.15.25","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"5.16.11","lessThanOrEqual":"5.16.*","status":"unaffected","versionType":"semver"},{"version":"5.17","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.13","versionEndExcluding":"5.15.25"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.13","versionEndExcluding":"5.16.11"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.13","versionEndExcluding":"5.17"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/c49c69dc9f3e699fa3150aca7b189eea707b4047"},{"url":"https://git.kernel.org/stable/c/3e11ef1903cf6c2fba35594b193a3570854d9e9e"},{"url":"https://git.kernel.org/stable/c/27f567c84f446048670376827e356f9c92033bf9"},{"url":"https://git.kernel.org/stable/c/26394fc118d6115390bd5b3a0fb17096271da227"}],"title":"ipv6: mcast: use rcu-safe version of ipv6_get_lladdr()","x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"providerMetadata":{"orgId":"af854a3a-2127-422b-91ae-364da2661108","shortName":"CVE","dateUpdated":"2024-08-03T15:25:01.616Z"},"title":"CVE Program Container","references":[{"url":"https://git.kernel.org/stable/c/3e11ef1903cf6c2fba35594b193a3570854d9e9e","tags":["x_transferred"]},{"url":"https://git.kernel.org/stable/c/27f567c84f446048670376827e356f9c92033bf9","tags":["x_transferred"]},{"url":"https://git.kernel.org/stable/c/26394fc118d6115390bd5b3a0fb17096271da227","tags":["x_transferred"]}]},{"metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2022-48785","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2024-09-10T17:00:04.966004Z"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2024-09-11T17:34:16.592Z"}}]}}