CVE-2024-41045

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Since\nthis relies on hrtimer_cancel as well, it is prone to the same deadlock\nsituation as the previous patch.\n\nIt would be sufficient to use hrtimer_try_to_cancel to fix this problem,\nas the timer cannot be enqueued after async_cancel_and_free. Once\nasync_cancel_and_free has been done, the timer must be reinitialized\nbefore it can be armed again. The callback running in parallel trying to\narm the timer will fail, and freeing bpf_hrtimer without waiting is\nsufficient (given kfree_rcu), and bpf_timer_cb will return\nHRTIMER_NORESTART, preventing the timer from being rearmed again.\n\nHowever, there exists a UAF scenario where the callback arms the timer\nbefore entering this function, such that if cancellation fails (due to\ntimer callback invoking this routine, or the target timer callback\nrunning concurrently). In such a case, if the timer expiration is\nsignificantly far in the future, the RCU grace period expiration\nhappening before it will free the bpf_hrtimer state and along with it\nthe struct hrtimer, that is enqueued.\n\nHence, it is clear cancellation needs to occur after\nasync_cancel_and_free, and yet it cannot be done inline due to deadlock\nissues. We thus modify bpf_timer_cancel_and_free to defer work to the\nglobal workqueue, adding a work_struct alongside rcu_head (both used at\n_different_ points of time, so can share space).\n\nUpdate existing code comments to reflect the new state of affairs."}], "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 vulnerability is reached by loading and running an attacker-authored BPF program via the bpf() syscall, which requires local access to the system. BPF is explicitly classified as a local attack vector in kernel scoring guidance.\nAC:L - The UAF is deterministic and fully attacker-scripted: the BPF callback arms its own timer with a far-future expiry and then deletes its own map element, guaranteeing the freed-while-enqueued hrtimer; no race the attacker cannot control is involved, and the deadlock variant is likewise attacker-orchestrated across two CPUs.\nPR:L - The bpf_timer_* helpers are gated by bpf_token_capable(CAP_BPF), which resolves to ns_capable() in a BPF-token user namespace, so an unprivileged user with a delegated bpffs token (common in container environments) can reach it. This matches established scoring for BPF verifier/helper CVEs.\nUI:N - The attacker loads and triggers the BPF timer entirely on their own; no victim action of any kind is needed.\nS:U - The freed object and the corrupted hrtimer state are both kernel-internal; the impact stays within the kernel's own security authority with no crossing into a hypervisor or IOMMU boundary.\nC:H - The freed bpf_hrtimer remains linked in the per-CPU hrtimer rbtree, so the timer subsystem keeps reading from reallocated heap memory, and controlling the freed slot gives an attacker a reliable kernel-memory read primitive enabling arbitrary disclosure.\nI:H - Enqueue/rebalance operations write rb_node and expiry fields into the freed object, and __run_hrtimer() calls a function pointer fetched from that freed memory, yielding both arbitrary write and control-flow hijack primitives after a heap spray.\nA:H - Both defects reliably take down the machine \u2014 the UAF corrupts the per-CPU hrtimer queue causing panics, and the mutual hrtimer_cancel() deadlock between two timer callbacks wedges CPUs in softirq context permanently."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["kernel/bpf/helpers.c"], "versions": [{"version": "b00628b1c7d595ae5b544e059c27b1f5828314b4", "lessThan": "7b27f15cab4c7d4f28c25b94a5284ad6d9d3695d", "status": "affected", "versionType": "git"}, {"version": "b00628b1c7d595ae5b544e059c27b1f5828314b4", "lessThan": "5eaa11c500ed07f505f86cec07d5593a71927e26", "status": "affected", "versionType": "git"}, {"version": "b00628b1c7d595ae5b544e059c27b1f5828314b4", "lessThan": "7aa5a19279c3639ae8b758b63f05d0c616a39fa1", "status": "affected", "versionType": "git"}, {"version": "b00628b1c7d595ae5b544e059c27b1f5828314b4", "lessThan": "a6fcd19d7eac1335eb76bc16b6a66b7f574d1d69", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["kernel/bpf/helpers.c"], "versions": [{"version": "5.15", "status": "affected"}, {"version": "0", "lessThan": "5.15", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.191", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.158", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.9.10", "lessThanOrEqual": "6.9.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.10", "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": "5.15", "versionEndExcluding": "6.1.191"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.6.158"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.9.10"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.10"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/7b27f15cab4c7d4f28c25b94a5284ad6d9d3695d"}, {"url": "https://git.kernel.org/stable/c/5eaa11c500ed07f505f86cec07d5593a71927e26"}, {"url": "https://git.kernel.org/stable/c/7aa5a19279c3639ae8b758b63f05d0c616a39fa1"}, {"url": "https://git.kernel.org/stable/c/a6fcd19d7eac1335eb76bc16b6a66b7f574d1d69"}], "title": "bpf: Defer work in bpf_timer_cancel_and_free", "x_generator": {"engine": "bippy-1.2.0"}}, "adp": [{"providerMetadata": {"orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2024-08-02T04:46:51.645Z"}, "title": "CVE Program Container", "references": [{"url": "https://git.kernel.org/stable/c/7aa5a19279c3639ae8b758b63f05d0c616a39fa1", "tags": ["x_transferred"]}, {"url": "https://git.kernel.org/stable/c/a6fcd19d7eac1335eb76bc16b6a66b7f574d1d69", "tags": ["x_transferred"]}]}, {"metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2024-41045", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2024-09-10T16:23:00.726132Z"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2024-09-11T17:34:02.451Z"}}]}}

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BPF is explicitly classified as a local attack vector in kernel scoring guidance.\nAC:L - The UAF is deterministic and fully attacker-scripted: the BPF callback arms its own timer with a far-future expiry and then deletes its own map element, guaranteeing the freed-while-enqueued hrtimer; no race the attacker cannot control is involved, and the deadlock variant is likewise attacker-orchestrated across two CPUs.\nPR:L - The bpf_timer_* helpers are gated by bpf_token_capable(CAP_BPF), which resolves to ns_capable() in a BPF-token user namespace, so an unprivileged user with a delegated bpffs token (common in container environments) can reach it. This matches established scoring for BPF verifier/helper CVEs.\nUI:N - The attacker loads and triggers the BPF timer entirely on their own; no victim action of any kind is needed.\nS:U - The freed object and the corrupted hrtimer state are both kernel-internal; the impact stays within the kernel's own security authority with no crossing into a hypervisor or IOMMU boundary.\nC:H - The freed bpf_hrtimer remains linked in the per-CPU hrtimer rbtree, so the timer subsystem keeps reading from reallocated heap memory, and controlling the freed slot gives an attacker a reliable kernel-memory read primitive enabling arbitrary disclosure.\nI:H - Enqueue/rebalance operations write rb_node and expiry fields into the freed object, and __run_hrtimer() calls a function pointer fetched from that freed memory, yielding both arbitrary write and control-flow hijack primitives after a heap spray.\nA:H - Both defects reliably take down the machine \u2014 the UAF corrupts the per-CPU hrtimer queue causing panics, and the mutual hrtimer_cancel() deadlock between two timer callbacks wedges CPUs in softirq context permanently."}]}], "affected": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "b00628b1c7d595ae5b544e059c27b1f5828314b4", "lessThan": "7b27f15cab4c7d4f28c25b94a5284ad6d9d3695d", "versionType": "git"}, {"status": "affected", "version": "b00628b1c7d595ae5b544e059c27b1f5828314b4", "lessThan": "5eaa11c500ed07f505f86cec07d5593a71927e26", "versionType": "git"}, {"status": "affected", "version": "b00628b1c7d595ae5b544e059c27b1f5828314b4", "lessThan": "7aa5a19279c3639ae8b758b63f05d0c616a39fa1", "versionType": "git"}, {"status": "affected", "version": "b00628b1c7d595ae5b544e059c27b1f5828314b4", "lessThan": "a6fcd19d7eac1335eb76bc16b6a66b7f574d1d69", "versionType": "git"}], "programFiles": ["kernel/bpf/helpers.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "5.15"}, {"status": "unaffected", "version": "0", "lessThan": "5.15", "versionType": "semver"}, {"status": "unaffected", "version": "6.1.191", "versionType": "semver", "lessThanOrEqual": "6.1.*"}, {"status": "unaffected", "version": "6.6.158", "versionType": "semver", "lessThanOrEqual": "6.6.*"}, {"status": "unaffected", "version": "6.9.10", "versionType": "semver", "lessThanOrEqual": "6.9.*"}, {"status": "unaffected", "version": "6.10", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["kernel/bpf/helpers.c"], "defaultStatus": "affected"}], "references": [{"url": "https://git.kernel.org/stable/c/7b27f15cab4c7d4f28c25b94a5284ad6d9d3695d"}, {"url": "https://git.kernel.org/stable/c/5eaa11c500ed07f505f86cec07d5593a71927e26"}, {"url": "https://git.kernel.org/stable/c/7aa5a19279c3639ae8b758b63f05d0c616a39fa1"}, {"url": "https://git.kernel.org/stable/c/a6fcd19d7eac1335eb76bc16b6a66b7f574d1d69"}], "x_generator": {"engine": "bippy-1.2.0"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Defer work in bpf_timer_cancel_and_free\n\nCurrently, the same case as previous patch (two timer callbacks trying\nto cancel each other) can be invoked through bpf_map_update_elem as\nwell, or more precisely, freeing map elements containing timers. Since\nthis relies on hrtimer_cancel as well, it is prone to the same deadlock\nsituation as the previous patch.\n\nIt would be sufficient to use hrtimer_try_to_cancel to fix this problem,\nas the timer cannot be enqueued after async_cancel_and_free. Once\nasync_cancel_and_free has been done, the timer must be reinitialized\nbefore it can be armed again. The callback running in parallel trying to\narm the timer will fail, and freeing bpf_hrtimer without waiting is\nsufficient (given kfree_rcu), and bpf_timer_cb will return\nHRTIMER_NORESTART, preventing the timer from being rearmed again.\n\nHowever, there exists a UAF scenario where the callback arms the timer\nbefore entering this function, such that if cancellation fails (due to\ntimer callback invoking this routine, or the target timer callback\nrunning concurrently). In such a case, if the timer expiration is\nsignificantly far in the future, the RCU grace period expiration\nhappening before it will free the bpf_hrtimer state and along with it\nthe struct hrtimer, that is enqueued.\n\nHence, it is clear cancellation needs to occur after\nasync_cancel_and_free, and yet it cannot be done inline due to deadlock\nissues. We thus modify bpf_timer_cancel_and_free to defer work to the\nglobal workqueue, adding a work_struct alongside rcu_head (both used at\n_different_ points of time, so can share space).\n\nUpdate existing code comments to reflect the new state of affairs."}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.1.191", "versionStartIncluding": "5.15"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.6.158", "versionStartIncluding": "5.15"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.9.10", "versionStartIncluding": "5.15"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.10", "versionStartIncluding": "5.15"}], "operator": "OR"}]}], "providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-30T12:18:44.387Z"}}}, "cveMetadata": {"cveId": "CVE-2024-41045", "state": "PUBLISHED", "dateUpdated": "2026-10-30T12:18:44.387Z", "dateReserved": "2024-07-12T12:17:45.624Z", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "datePublished": "2024-07-29T14:32:02.866Z", "assignerShortName": "Linux"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["kernel/bpf/helpers.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "7b27f15cab4c7d4f28c25b94a5284ad6d9d3695d", "status": "affected", "version": "b00628b1c7d595ae5b544e059c27b1f5828314b4", "versionType": "git"}, {"lessThan": "5eaa11c500ed07f505f86cec07d5593a71927e26", "status": "affected", "version": "b00628b1c7d595ae5b544e059c27b1f5828314b4", "versionType": "git"}, {"lessThan": "7aa5a19279c3639ae8b758b63f05d0c616a39fa1", "status": "affected", "version": "b00628b1c7d595ae5b544e059c27b1f5828314b4", "versionType": "git"}, {"lessThan": "a6fcd19d7eac1335eb76bc16b6a66b7f574d1d69", "status": "affected", "version": "b00628b1c7d595ae5b544e059c27b1f5828314b4", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["kernel/bpf/helpers.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "5.15"}, {"lessThan": "5.15", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.191", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.158", "versionType": "semver"}, {"lessThanOrEqual": "6.9.*", "status": "unaffected", "version": "6.9.10", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "6.10", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "C89C12B4-1B68-4A90-AE7B-1DBF780ABB17", "versionEndExcluding": "6.9.10", "versionStartIncluding": "5.15", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.10:rc1:*:*:*:*:*:*", "matchCriteriaId": "2EBB4392-5FA6-4DA9-9772-8F9C750109FA", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.10:rc2:*:*:*:*:*:*", "matchCriteriaId": "331C2F14-12C7-45D5-893D-8C52EE38EA10", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.10:rc3:*:*:*:*:*:*", "matchCriteriaId": "3173713D-909A-4DD3-9DD4-1E171EB057EE", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.10:rc4:*:*:*:*:*:*", "matchCriteriaId": "79F18AFA-40F7-43F0-BA30-7BDB65F918B9", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.10:rc5:*:*:*:*:*:*", "matchCriteriaId": "BD973AA4-A789-49BD-8D57-B2846935D3C7", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.10:rc6:*:*:*:*:*:*", "matchCriteriaId": "8F3E9E0C-AC3E-4967-AF80-6483E8AB0078", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.10:rc7:*:*:*:*:*:*", "matchCriteriaId": "11AF4CB9-F697-4EA4-8903-8F9417EFDA8E", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Defer work in bpf_timer_cancel_and_free\n\nCurrently, the same case as previous patch (two timer callbacks trying\nto cancel each other) can be invoked through bpf_map_update_elem as\nwell, or more precisely, freeing map elements containing timers. Since\nthis relies on hrtimer_cancel as well, it is prone to the same deadlock\nsituation as the previous patch.\n\nIt would be sufficient to use hrtimer_try_to_cancel to fix this problem,\nas the timer cannot be enqueued after async_cancel_and_free. Once\nasync_cancel_and_free has been done, the timer must be reinitialized\nbefore it can be armed again. The callback running in parallel trying to\narm the timer will fail, and freeing bpf_hrtimer without waiting is\nsufficient (given kfree_rcu), and bpf_timer_cb will return\nHRTIMER_NORESTART, preventing the timer from being rearmed again.\n\nHowever, there exists a UAF scenario where the callback arms the timer\nbefore entering this function, such that if cancellation fails (due to\ntimer callback invoking this routine, or the target timer callback\nrunning concurrently). In such a case, if the timer expiration is\nsignificantly far in the future, the RCU grace period expiration\nhappening before it will free the bpf_hrtimer state and along with it\nthe struct hrtimer, that is enqueued.\n\nHence, it is clear cancellation needs to occur after\nasync_cancel_and_free, and yet it cannot be done inline due to deadlock\nissues. We thus modify bpf_timer_cancel_and_free to defer work to the\nglobal workqueue, adding a work_struct alongside rcu_head (both used at\n_different_ points of time, so can share space).\n\nUpdate existing code comments to reflect the new state of affairs."}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: bpf: Aplazar el trabajo en bpf_timer_cancel_and_free Actualmente, el mismo caso del parche anterior (dos devoluciones de llamada de temporizador que intentan cancelarse entre s\u00ed) tambi\u00e9n se puede invocar a trav\u00e9s de bpf_map_update_elem, o m\u00e1s precisamente, liberando mapa elementos que contienen temporizadores. Dado que esto tambi\u00e9n depende de hrtimer_cancel, es propenso a la misma situaci\u00f3n de punto muerto que el parche anterior. Ser\u00eda suficiente usar hrtimer_try_to_cancel para solucionar este problema, ya que el temporizador no se puede poner en cola despu\u00e9s de async_cancel_and_free. Una vez que se haya realizado async_cancel_and_free, el temporizador debe reinicializarse antes de poder armarse nuevamente. La devoluci\u00f3n de llamada que se ejecuta en paralelo al intentar armar el temporizador fallar\u00e1, y liberar bpf_hrtimer sin esperar es suficiente (dado kfree_rcu), y bpf_timer_cb devolver\u00e1 HRTIMER_NORESTART, evitando que el temporizador se rearme nuevamente. Sin embargo, existe un escenario UAF en el que la devoluci\u00f3n de llamada arma el temporizador antes de ingresar a esta funci\u00f3n, de modo que si la cancelaci\u00f3n falla (debido a que la devoluci\u00f3n de llamada del temporizador invoca esta rutina o la devoluci\u00f3n de llamada del temporizador de destino se ejecuta simult\u00e1neamente). En tal caso, si la expiraci\u00f3n del temporizador est\u00e1 significativamente lejos en el futuro, la expiraci\u00f3n del per\u00edodo de gracia de RCU que ocurra antes liberar\u00e1 el estado bpf_hrtimer y junto con \u00e9l la estructura hrtimer, que est\u00e1 en cola. Por lo tanto, est\u00e1 claro que la cancelaci\u00f3n debe ocurrir despu\u00e9s de async_cancel_and_free y, sin embargo, no se puede realizar en l\u00ednea debido a problemas de interbloqueo. Por lo tanto, modificamos bpf_timer_cancel_and_free para diferir el trabajo a la cola de trabajo global, agregando un work_struct junto con rcu_head (ambos usados en _diferentes_ puntos de tiempo, por lo que pueden compartir espacio). Actualice los comentarios del c\u00f3digo existente para reflejar la nueva situaci\u00f3n."}], "id": "CVE-2024-41045", "lastModified": "2026-10-30T13:17:30.927", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.9, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}, {"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.9, "source": "nvd@nist.gov", "type": "Primary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2024-41045", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2024-09-10T16:23:00.726132Z", "version": "2.0.3"}}]}, "published": "2024-07-29T15:15:12.873", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/5eaa11c500ed07f505f86cec07d5593a71927e26"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/7aa5a19279c3639ae8b758b63f05d0c616a39fa1"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/7b27f15cab4c7d4f28c25b94a5284ad6d9d3695d"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/a6fcd19d7eac1335eb76bc16b6a66b7f574d1d69"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/7aa5a19279c3639ae8b758b63f05d0c616a39fa1"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/a6fcd19d7eac1335eb76bc16b6a66b7f574d1d69"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-416"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"bugzilla": {"description": "kernel: bpf: Defer work in bpf_timer_cancel_and_free", "id": "2300415", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2300415"}, "csaw": false, "cvss3": {"cvss3_base_score": "4.1", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-833", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nbpf: Defer work in bpf_timer_cancel_and_free\nCurrently, the same case as previous patch (two timer callbacks trying\nto cancel each other) can be invoked through bpf_map_update_elem as\nwell, or more precisely, freeing map elements containing timers. Since\nthis relies on hrtimer_cancel as well, it is prone to the same deadlock\nsituation as the previous patch.\nIt would be sufficient to use hrtimer_try_to_cancel to fix this problem,\nas the timer cannot be enqueued after async_cancel_and_free. Once\nasync_cancel_and_free has been done, the timer must be reinitialized\nbefore it can be armed again. The callback running in parallel trying to\narm the timer will fail, and freeing bpf_hrtimer without waiting is\nsufficient (given kfree_rcu), and bpf_timer_cb will return\nHRTIMER_NORESTART, preventing the timer from being rearmed again.\nHowever, there exists a UAF scenario where the callback arms the timer\nbefore entering this function, such that if cancellation fails (due to\ntimer callback invoking this routine, or the target timer callback\nrunning concurrently). In such a case, if the timer expiration is\nsignificantly far in the future, the RCU grace period expiration\nhappening before it will free the bpf_hrtimer state and along with it\nthe struct hrtimer, that is enqueued.\nHence, it is clear cancellation needs to occur after\nasync_cancel_and_free, and yet it cannot be done inline due to deadlock\nissues. We thus modify bpf_timer_cancel_and_free to defer work to the\nglobal workqueue, adding a work_struct alongside rcu_head (both used at\n_different_ points of time, so can share space).\nUpdate existing code comments to reflect the new state of affairs."], "name": "CVE-2024-41045", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Out of support scope", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Will not fix", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Will not fix", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2024-07-29T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2024-41045\nhttps://nvd.nist.gov/vuln/detail/CVE-2024-41045\nhttps://lore.kernel.org/linux-cve-announce/2024072925-CVE-2024-41045-6cc1@gregkh/T"], "threat_severity": "Moderate"}

{"created": "2025-07-12T22:45:02.071646+00:00", "updated": "2025-07-12T22:45:02.071714+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}