{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2024-50126", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-10-21T19:36:19.954Z", "datePublished": "2024-11-05T17:10:53.741Z", "dateUpdated": "2026-08-05T11:41:52.047Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T11:41:52.047Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: sched: use RCU read-side critical section in taprio_dump()\n\nFix possible use-after-free in 'taprio_dump()' by adding RCU\nread-side critical section there. Never seen on x86 but\nfound on a KASAN-enabled arm64 system when investigating\nhttps://syzkaller.appspot.com/bug?extid=b65e0af58423fc8a73aa:\n\n[T15862] BUG: KASAN: slab-use-after-free in taprio_dump+0xa0c/0xbb0\n[T15862] Read of size 4 at addr ffff0000d4bb88f8 by task repro/15862\n[T15862]\n[T15862] CPU: 0 UID: 0 PID: 15862 Comm: repro Not tainted 6.11.0-rc1-00293-gdefaf1a2113a-dirty #2\n[T15862] Hardware name: QEMU QEMU Virtual Machine, BIOS edk2-20240524-5.fc40 05/24/2024\n[T15862] Call trace:\n[T15862] dump_backtrace+0x20c/0x220\n[T15862] show_stack+0x2c/0x40\n[T15862] dump_stack_lvl+0xf8/0x174\n[T15862] print_report+0x170/0x4d8\n[T15862] kasan_report+0xb8/0x1d4\n[T15862] __asan_report_load4_noabort+0x20/0x2c\n[T15862] taprio_dump+0xa0c/0xbb0\n[T15862] tc_fill_qdisc+0x540/0x1020\n[T15862] qdisc_notify.isra.0+0x330/0x3a0\n[T15862] tc_modify_qdisc+0x7b8/0x1838\n[T15862] rtnetlink_rcv_msg+0x3c8/0xc20\n[T15862] netlink_rcv_skb+0x1f8/0x3d4\n[T15862] rtnetlink_rcv+0x28/0x40\n[T15862] netlink_unicast+0x51c/0x790\n[T15862] netlink_sendmsg+0x79c/0xc20\n[T15862] __sock_sendmsg+0xe0/0x1a0\n[T15862] ____sys_sendmsg+0x6c0/0x840\n[T15862] ___sys_sendmsg+0x1ac/0x1f0\n[T15862] __sys_sendmsg+0x110/0x1d0\n[T15862] __arm64_sys_sendmsg+0x74/0xb0\n[T15862] invoke_syscall+0x88/0x2e0\n[T15862] el0_svc_common.constprop.0+0xe4/0x2a0\n[T15862] do_el0_svc+0x44/0x60\n[T15862] el0_svc+0x50/0x184\n[T15862] el0t_64_sync_handler+0x120/0x12c\n[T15862] el0t_64_sync+0x190/0x194\n[T15862]\n[T15862] Allocated by task 15857:\n[T15862] kasan_save_stack+0x3c/0x70\n[T15862] kasan_save_track+0x20/0x3c\n[T15862] kasan_save_alloc_info+0x40/0x60\n[T15862] __kasan_kmalloc+0xd4/0xe0\n[T15862] __kmalloc_cache_noprof+0x194/0x334\n[T15862] taprio_change+0x45c/0x2fe0\n[T15862] tc_modify_qdisc+0x6a8/0x1838\n[T15862] rtnetlink_rcv_msg+0x3c8/0xc20\n[T15862] netlink_rcv_skb+0x1f8/0x3d4\n[T15862] rtnetlink_rcv+0x28/0x40\n[T15862] netlink_unicast+0x51c/0x790\n[T15862] netlink_sendmsg+0x79c/0xc20\n[T15862] __sock_sendmsg+0xe0/0x1a0\n[T15862] ____sys_sendmsg+0x6c0/0x840\n[T15862] ___sys_sendmsg+0x1ac/0x1f0\n[T15862] __sys_sendmsg+0x110/0x1d0\n[T15862] __arm64_sys_sendmsg+0x74/0xb0\n[T15862] invoke_syscall+0x88/0x2e0\n[T15862] el0_svc_common.constprop.0+0xe4/0x2a0\n[T15862] do_el0_svc+0x44/0x60\n[T15862] el0_svc+0x50/0x184\n[T15862] el0t_64_sync_handler+0x120/0x12c\n[T15862] el0t_64_sync+0x190/0x194\n[T15862]\n[T15862] Freed by task 6192:\n[T15862] kasan_save_stack+0x3c/0x70\n[T15862] kasan_save_track+0x20/0x3c\n[T15862] kasan_save_free_info+0x4c/0x80\n[T15862] poison_slab_object+0x110/0x160\n[T15862] __kasan_slab_free+0x3c/0x74\n[T15862] kfree+0x134/0x3c0\n[T15862] taprio_free_sched_cb+0x18c/0x220\n[T15862] rcu_core+0x920/0x1b7c\n[T15862] rcu_core_si+0x10/0x1c\n[T15862] handle_softirqs+0x2e8/0xd64\n[T15862] __do_softirq+0x14/0x20" } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The vulnerable `taprio_dump()` is reached only through rtnetlink socket messages (RTM_GETQDISC/RTM_NEWQDISC) issued via sendmsg() by a local process, matching the tc/netlink qdisc = Local classification.\nAC:L - The attacker drives both sides of the race — one thread loops `tc qdisc show` while another loops taprio_change() (which call_rcu()s the replaced schedule), and the attacker picks a huge entry list plus a microsecond cycle_time to widen the dump window and make advance_sched() fire continuously.\nPR:L - The dump side (RTM_GETQDISC) requires no capability at all since rtnetlink_rcv_msg() skips the CAP_NET_ADMIN check for RTNL_KIND_GET, and installing the taprio qdisc needs only CAP_NET_ADMIN in a namespace obtainable by any unprivileged user via `unshare -Urn`.\nUI:N - The attacker triggers the entire sequence — qdisc creation, schedule replacement, and dump — from their own processes with no victim action required.\nS:U - The use-after-free occurs in kernel slab memory and its impact stays within the kernel's own security authority, with no crossing of a VM, IOMMU, or sandbox boundary.\nC:H - Freed `sched_gate_list`/`sched_entry` bytes (base_time, cycle_time, max_sdu[], and per-entry index/command/gate_mask/interval) are copied verbatim into the netlink reply, so after heap reallocation the attacker reads back arbitrary kernel heap contents, and a controlled `entries` list head turns the traversal into a targeted read primitive.\nI:H - This is a slab use-after-free on an object the attacker can reclaim and control via heap spraying, and the resulting corrupted list traversal is the classic building block for escalating to control-flow hijack rather than a bounded read.\nA:H - Walking a freed and recycled entry list dereferences poisoned or attacker-influenced pointers, producing the KASAN slab-use-after-free/oops seen in the report and a reliably repeatable kernel crash." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/sched/sch_taprio.c" ], "versions": [ { "version": "18cdd2f0998a4967b1fff4c43ed9aef049e42c39", "lessThan": "b911fa9e92ee586e36479ad57b88f20471acaca1", "status": "affected", "versionType": "git" }, { "version": "18cdd2f0998a4967b1fff4c43ed9aef049e42c39", "lessThan": "5d282467245f267c0b9ada3f7f309ff838521536", "status": "affected", "versionType": "git" }, { "version": "18cdd2f0998a4967b1fff4c43ed9aef049e42c39", "lessThan": "e4369cb6acf6b895ac2453cc1cdf2f4326122c6d", "status": "affected", "versionType": "git" }, { "version": "18cdd2f0998a4967b1fff4c43ed9aef049e42c39", "lessThan": "b22db8b8befe90b61c98626ca1a2fbb0505e9fe3", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/sched/sch_taprio.c" ], "versions": [ { "version": "6.1", "status": "affected" }, { "version": "0", "lessThan": "6.1", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.117", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.59", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.11.6", "lessThanOrEqual": "6.11.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12", "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": "6.1", "versionEndExcluding": "6.1.117" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1", "versionEndExcluding": "6.6.59" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1", "versionEndExcluding": "6.11.6" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1", "versionEndExcluding": "6.12" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/b911fa9e92ee586e36479ad57b88f20471acaca1" }, { "url": "https://git.kernel.org/stable/c/5d282467245f267c0b9ada3f7f309ff838521536" }, { "url": "https://git.kernel.org/stable/c/e4369cb6acf6b895ac2453cc1cdf2f4326122c6d" }, { "url": "https://git.kernel.org/stable/c/b22db8b8befe90b61c98626ca1a2fbb0505e9fe3" } ], "title": "net: sched: use RCU read-side critical section in taprio_dump()", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "cvssV3_1": { "scope": "UNCHANGED", "version": "3.1", "baseScore": 7.8, "attackVector": "LOCAL", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "HIGH" } }, { "other": { "type": "ssvc", "content": { "id": "CVE-2024-50126", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "total" } ], "version": "2.0.3", "timestamp": "2024-12-11T14:28:25.069183Z" } } } ], "problemTypes": [ { "descriptions": [ { "lang": "en", "type": "CWE", "cweId": "CWE-416", "description": "CWE-416 Use After Free" } ] } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2024-12-11T14:58:33.520Z" } }, { "title": "CVE Program Container", "references": [ { "url": "https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html" } ], "providerMetadata": { "orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2025-11-03T22:25:47.069Z" } } ] } }