CVE-2024-35969

{"id": "CVE-2024-35969", "metrics": {"cvssMetricV31": [{"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.5, "attackVector": "LOCAL", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 1.8}]}, "published": "2024-05-20T10:15:11.780", "references": [{"url": "https://git.kernel.org/stable/c/01b11a0566670612bd464a932e5ac2eae53d8652", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/3fb02ec57ead2891a2306af8c51a306bc5945e70", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/4b19e9507c275de0cfe61c24db69179dc52cf9fb", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/6cdb20c342cd0193d3e956e3d83981d0f438bb83", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/7633c4da919ad51164acbf1aa322cc1a3ead6129", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/b4b3b69a19016d4e7fbdbd1dbcc184915eb862e1", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/cca606e14264098cba65efa82790825dbf69e903", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/de76ae9ea1a6cf9e77fcec4f2df2904e26c23ceb", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/01b11a0566670612bd464a932e5ac2eae53d8652", "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/3fb02ec57ead2891a2306af8c51a306bc5945e70", "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/4b19e9507c275de0cfe61c24db69179dc52cf9fb", "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/6cdb20c342cd0193d3e956e3d83981d0f438bb83", "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/7633c4da919ad51164acbf1aa322cc1a3ead6129", "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/b4b3b69a19016d4e7fbdbd1dbcc184915eb862e1", "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/cca606e14264098cba65efa82790825dbf69e903", "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://git.kernel.org/stable/c/de76ae9ea1a6cf9e77fcec4f2df2904e26c23ceb", "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html", "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://lists.debian.org/debian-lts-announce/2024/06/msg00020.html", "source": "af854a3a-2127-422b-91ae-364da2661108"}], "vulnStatus": "Awaiting Analysis", "weaknesses": [{"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "description": [{"lang": "en", "value": "CWE-770"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: fix race condition between ipv6_get_ifaddr and ipv6_del_addr\n\nAlthough ipv6_get_ifaddr walks inet6_addr_lst under the RCU lock, it\nstill means hlist_for_each_entry_rcu can return an item that got removed\nfrom the list. The memory itself of such item is not freed thanks to RCU\nbut nothing guarantees the actual content of the memory is sane.\n\nIn particular, the reference count can be zero. This can happen if\nipv6_del_addr is called in parallel. ipv6_del_addr removes the entry\nfrom inet6_addr_lst (hlist_del_init_rcu(&ifp->addr_lst)) and drops all\nreferences (__in6_ifa_put(ifp) + in6_ifa_put(ifp)). With bad enough\ntiming, this can happen:\n\n1. In ipv6_get_ifaddr, hlist_for_each_entry_rcu returns an entry.\n\n2. Then, the whole ipv6_del_addr is executed for the given entry. The\n reference count drops to zero and kfree_rcu is scheduled.\n\n3. ipv6_get_ifaddr continues and tries to increments the reference count\n (in6_ifa_hold).\n\n4. The rcu is unlocked and the entry is freed.\n\n5. The freed entry is returned.\n\nPrevent increasing of the reference count in such case. The name\nin6_ifa_hold_safe is chosen to mimic the existing fib6_info_hold_safe.\n\n[ 41.506330] refcount_t: addition on 0; use-after-free.\n[ 41.506760] WARNING: CPU: 0 PID: 595 at lib/refcount.c:25 refcount_warn_saturate+0xa5/0x130\n[ 41.507413] Modules linked in: veth bridge stp llc\n[ 41.507821] CPU: 0 PID: 595 Comm: python3 Not tainted 6.9.0-rc2.main-00208-g49563be82afa #14\n[ 41.508479] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)\n[ 41.509163] RIP: 0010:refcount_warn_saturate+0xa5/0x130\n[ 41.509586] Code: ad ff 90 0f 0b 90 90 c3 cc cc cc cc 80 3d c0 30 ad 01 00 75 a0 c6 05 b7 30 ad 01 01 90 48 c7 c7 38 cc 7a 8c e8 cc 18 ad ff 90 <0f> 0b 90 90 c3 cc cc cc cc 80 3d 98 30 ad 01 00 0f 85 75 ff ff ff\n[ 41.510956] RSP: 0018:ffffbda3c026baf0 EFLAGS: 00010282\n[ 41.511368] RAX: 0000000000000000 RBX: ffff9e9c46914800 RCX: 0000000000000000\n[ 41.511910] RDX: ffff9e9c7ec29c00 RSI: ffff9e9c7ec1c900 RDI: ffff9e9c7ec1c900\n[ 41.512445] RBP: ffff9e9c43660c9c R08: 0000000000009ffb R09: 00000000ffffdfff\n[ 41.512998] R10: 00000000ffffdfff R11: ffffffff8ca58a40 R12: ffff9e9c4339a000\n[ 41.513534] R13: 0000000000000001 R14: ffff9e9c438a0000 R15: ffffbda3c026bb48\n[ 41.514086] FS: 00007fbc4cda1740(0000) GS:ffff9e9c7ec00000(0000) knlGS:0000000000000000\n[ 41.514726] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[ 41.515176] CR2: 000056233b337d88 CR3: 000000000376e006 CR4: 0000000000370ef0\n[ 41.515713] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\n[ 41.516252] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\n[ 41.516799] Call Trace:\n[ 41.517037] <TASK>\n[ 41.517249] ? __warn+0x7b/0x120\n[ 41.517535] ? refcount_warn_saturate+0xa5/0x130\n[ 41.517923] ? report_bug+0x164/0x190\n[ 41.518240] ? handle_bug+0x3d/0x70\n[ 41.518541] ? exc_invalid_op+0x17/0x70\n[ 41.520972] ? asm_exc_invalid_op+0x1a/0x20\n[ 41.521325] ? refcount_warn_saturate+0xa5/0x130\n[ 41.521708] ipv6_get_ifaddr+0xda/0xe0\n[ 41.522035] inet6_rtm_getaddr+0x342/0x3f0\n[ 41.522376] ? __pfx_inet6_rtm_getaddr+0x10/0x10\n[ 41.522758] rtnetlink_rcv_msg+0x334/0x3d0\n[ 41.523102] ? netlink_unicast+0x30f/0x390\n[ 41.523445] ? __pfx_rtnetlink_rcv_msg+0x10/0x10\n[ 41.523832] netlink_rcv_skb+0x53/0x100\n[ 41.524157] netlink_unicast+0x23b/0x390\n[ 41.524484] netlink_sendmsg+0x1f2/0x440\n[ 41.524826] __sys_sendto+0x1d8/0x1f0\n[ 41.525145] __x64_sys_sendto+0x1f/0x30\n[ 41.525467] do_syscall_64+0xa5/0x1b0\n[ 41.525794] entry_SYSCALL_64_after_hwframe+0x72/0x7a\n[ 41.526213] RIP: 0033:0x7fbc4cfcea9a\n[ 41.526528] Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 f3 0f 1e fa 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 15 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 7e c3 0f 1f 44 00 00 41 54 48 83 ec 30 44 89\n[ 41.527942] RSP: 002b:00007f\n---truncated---"}, {"lang": "es", "value": "En el kernel de Linux, se resolvi\u00f3 la siguiente vulnerabilidad: ipv6: corrige la condici\u00f3n de ejecuci\u00f3n entre ipv6_get_ifaddr e ipv6_del_addr .Aunque ipv6_get_ifaddr recorre inet6_addr_lst bajo el bloqueo de RCU, todav\u00eda significa que hlist_for_each_entry_rcu puede devolver un elemento que se elimin\u00f3 de la lista. La memoria en s\u00ed de dicho elemento no se libera gracias a RCU, pero nada garantiza que el contenido real de la memoria sea sano. En particular, el recuento de referencia puede ser cero. Esto puede suceder si se llama a ipv6_del_addr en paralelo. ipv6_del_addr elimina la entrada de inet6_addr_lst (hlist_del_init_rcu(&amp;ifp-&gt;addr_lst)) y elimina todas las referencias (__in6_ifa_put(ifp) + in6_ifa_put(ifp)). En un momento bastante malo, esto puede suceder: 1. En ipv6_get_ifaddr, hlist_for_each_entry_rcu devuelve una entrada. 2. Luego, se ejecuta todo el ipv6_del_addr para la entrada dada. El recuento de referencias cae a cero y se programa kfree_rcu. 3. ipv6_get_ifaddr contin\u00faa e intenta incrementar el recuento de referencias (in6_ifa_hold). 4. Se desbloquea la rcu y se libera la entrada. 5. Se devuelve la entrada liberada. Evite el aumento del recuento de referencia en tal caso. El nombre in6_ifa_hold_safe se elige para imitar el fib6_info_hold_safe existente. [41.506330] refcount_t: suma en 0; uso despu\u00e9s de la liberaci\u00f3n. [ 41.506760] ADVERTENCIA: CPU: 0 PID: 595 en lib/refcount.c:25 refcount_warn_saturate+0xa5/0x130 [ 41.507413] M\u00f3dulos vinculados en: veth bridge stp llc [ 41.507821] CPU: 0 PID: 595 Comm: python3 No contaminado 6.9 .0-rc2.main-00208-g49563be82afa #14 [ 41.508479] Nombre del hardware: PC est\u00e1ndar QEMU (i440FX + PIIX, 1996) [ 41.509163] RIP: 0010:refcount_warn_saturate+0xa5/0x130 [ 41.509586] C\u00f3digo: ad ff 90 0f 0b 90 90 c3 cc cc cc 80 3d c0 30 ad 01 00 75 a0 c6 05 b7 30 ad 01 01 90 48 c7 c7 38 cc 7a 8c e8 cc 18 ad ff 90 &lt;0f&gt; 0b 90 90 c3 cc cc cc 80 3d 98 30 ad 01 00 0f 85 75 ff ff ff [ 41.510956] RSP: 0018:ffffbda3c026baf0 EFLAGS: 00010282 [ 41.511368] RAX: 0000000000000000 RBX: 800 RCX: 0000000000000000 [ 41.511910] RDX: ffff9e9c7ec29c00 RSI: ffff9e9c7ec1c900 RDI: ffff9e9c7ec1c900 [ 41.512445] RBP : ffff9e9c43660c9c R08: 0000000000009ffb R09: 00000000ffffdfff [ 41.512998] R10: 00000000ffffdfff R11: fffffff8ca58a40 R12: ffff9e9c4339a000 [ 41 .513534] R13: 0000000000000001 R14: ffff9e9c438a0000 R15: ffffbda3c026bb48 [ 41.514086] FS: 00007fbc4cda1740(0000) GS:ffff9e9c7ec00000(0000) lGS:0000000000000000 [ 41.514726] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 41.515176] CR2: 000056233b337d88 CR3: 000000000376e006 CR4: 0000000000370ef 0 [ 41.515713] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 41.516252] DR3: 00000000000000000 DR6: 00000000ffe0ff0 DR7 : 0000000000000400 [ 41.516799] Seguimiento de llamadas: [ 41.517037] [ 41.517249] ? __warn+0x7b/0x120 [ 41.517535] ? refcount_warn_saturate+0xa5/0x130 [41.517923]? report_bug+0x164/0x190 [41.518240]? handle_bug+0x3d/0x70 [41.518541]? exc_invalid_op+0x17/0x70 [41.520972]? asm_exc_invalid_op+0x1a/0x20 [41.521325]? refcount_warn_saturate+0xa5/0x130 [ 41.521708] ipv6_get_ifaddr+0xda/0xe0 [ 41.522035] inet6_rtm_getaddr+0x342/0x3f0 [ 41.522376] ? __pfx_inet6_rtm_getaddr+0x10/0x10 [ 41.522758] rtnetlink_rcv_msg+0x334/0x3d0 [ 41.523102] ? netlink_unicast+0x30f/0x390 [41.523445]? __pfx_rtnetlink_rcv_msg+0x10/0x10 [ 41.523832] netlink_rcv_skb+0x53/0x100 [ 41.524157] netlink_unicast+0x23b/0x390 [ 41.524484] netlink_sendmsg+0x1f2/0x440 [ 41. 524826] __sys_sendto+0x1d8/0x1f0 [ 41.525145] __x64_sys_sendto+0x1f/0x30 [ 41.525467] do_syscall_64+ 0xa5/0x1b0 [41.525794] Entry_SYSCALL_64_after_hwframe+0x72/0x7a [41.526213] RIP: 0033:0x7fbc4cfcea9a [41.526528] C\u00f3digo: d8 64 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 f3 0f 1e fa 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 15 b8 2c 00 00 00 0f 05 &lt;48&gt; 3d 00 f0 ff ff 77 7e c3 0f 1f 44 00 00 41 54 48 83 ec 30 44 89 [ 41.527942] 002b:00007f-- -truncado---"}], "lastModified": "2024-11-21T09:21:19.273", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}