CVE-2025-21876

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Fix\nit by ensuring the dmar_global_lock lock is held when traversing the\ndrhd list.\n\nWithout this fix, the following warning is triggered:\n =============================\n WARNING: suspicious RCU usage\n 6.14.0-rc3 #55 Not tainted\n -----------------------------\n drivers/iommu/intel/dmar.c:2046 RCU-list traversed in non-reader section!!\n other info that might help us debug this:\n rcu_scheduler_active = 1, debug_locks = 1\n 2 locks held by cpuhp/1/23:\n #0: ffffffff84a67c50 (cpu_hotplug_lock){++++}-{0:0}, at: cpuhp_thread_fun+0x87/0x2c0\n #1: ffffffff84a6a380 (cpuhp_state-up){+.+.}-{0:0}, at: cpuhp_thread_fun+0x87/0x2c0\n stack backtrace:\n CPU: 1 UID: 0 PID: 23 Comm: cpuhp/1 Not tainted 6.14.0-rc3 #55\n Call Trace:\n <TASK>\n dump_stack_lvl+0xb7/0xd0\n lockdep_rcu_suspicious+0x159/0x1f0\n ? __pfx_enable_drhd_fault_handling+0x10/0x10\n enable_drhd_fault_handling+0x151/0x180\n cpuhp_invoke_callback+0x1df/0x990\n cpuhp_thread_fun+0x1ea/0x2c0\n smpboot_thread_fn+0x1f5/0x2e0\n ? __pfx_smpboot_thread_fn+0x10/0x10\n kthread+0x12a/0x2d0\n ? __pfx_kthread+0x10/0x10\n ret_from_fork+0x4a/0x60\n ? __pfx_kthread+0x10/0x10\n ret_from_fork_asm+0x1a/0x30\n </TASK>\n\nHolding the lock in enable_drhd_fault_handling() triggers a lockdep splat\nabout a possible deadlock between dmar_global_lock and cpu_hotplug_lock.\nThis is avoided by not holding dmar_global_lock when calling\niommu_device_register(), which initiates the device probe process."}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H", "baseScore": 8.8, "baseSeverity": "HIGH"}, "scenarios": [{"lang": "en", "value": "AV:L - The vulnerable code is an Intel VT-d CPU-hotplug startup callback reached only through local machine state transitions (sysfs CPU online, suspend/resume), with no network-facing input path.\nAC:L - The unsynchronized RCU-list traversal executes on every CPU-online event, which a local attacker can trigger repeatedly and at will via CPU hotplug or suspend/resume cycles, so the unprotected window is reached reliably rather than depending on chance.\nPR:L - Writing /sys/devices/system/cpu/N/online needs root, but the same callback runs on every resume from suspend, and on typical desktop/laptop deployments an unprivileged local session can request suspend through logind, so no elevated privileges are strictly required.\nUI:N - The attacker initiates the CPU-online or suspend/resume transition themselves; no action by any other user is needed.\nS:C - The corrupted object is the Intel IOMMU descriptor, and writes through a dangling iommu->reg reach DMAR hardware register windows, so the impact extends past the kernel's own authority into the DMA-isolation boundary that protects host memory from devices and assigned-device guests.\nC:H - Traversing a freed dmar_drhd_unit/intel_iommu yields a use-after-free whose reclaimed contents supply the MMIO base used by readl() in dmar_fault(), giving an arbitrary kernel/MMIO read primitive.\nI:H - The same stale iommu->reg is used for writel() to DMAR_FSTS_REG and the fault-event registers, providing an attacker-influenced arbitrary write that can corrupt kernel data or IOMMU control state.\nA:H - Dereferencing the freed DMAR unit oopses the kernel, and a non-zero return from the callback aborts the CPU-online operation, so the bug causes crashes and denial of service even when not fully exploited."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/iommu/intel/dmar.c", "drivers/iommu/intel/iommu.c"], "versions": [{"version": "d74169ceb0d2e32438946a2f1f9fc8c803304bd6", "lessThan": "4117c72938493a77ab53cc4b8284be8fb6ec8065", "status": "affected", "versionType": "git"}, {"version": "d74169ceb0d2e32438946a2f1f9fc8c803304bd6", "lessThan": "c603ccbe91d189849e1439134598ec567088dcec", "status": "affected", "versionType": "git"}, {"version": "d74169ceb0d2e32438946a2f1f9fc8c803304bd6", "lessThan": "b150654f74bf0df8e6a7936d5ec51400d9ec06d8", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/iommu/intel/dmar.c", "drivers/iommu/intel/iommu.c"], "versions": [{"version": "6.10", "status": "affected"}, {"version": "0", "lessThan": "6.10", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.18", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.13.6", "lessThanOrEqual": "6.13.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.14", "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": "6.10", "versionEndExcluding": "6.12.18"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.10", "versionEndExcluding": "6.13.6"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.10", "versionEndExcluding": "6.14"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/4117c72938493a77ab53cc4b8284be8fb6ec8065"}, {"url": "https://git.kernel.org/stable/c/c603ccbe91d189849e1439134598ec567088dcec"}, {"url": "https://git.kernel.org/stable/c/b150654f74bf0df8e6a7936d5ec51400d9ec06d8"}], "title": "iommu/vt-d: Fix suspicious RCU usage", "x_generator": {"engine": "bippy-1.2.0"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2025-21876", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "total"}], "version": "2.0.3", "timestamp": "2026-10-15T21:43:25.342939Z"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-15T21:51:54.560Z"}}]}}

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Fix\nit by ensuring the dmar_global_lock lock is held when traversing the\ndrhd list.\n\nWithout this fix, the following warning is triggered:\n =============================\n WARNING: suspicious RCU usage\n 6.14.0-rc3 #55 Not tainted\n -----------------------------\n drivers/iommu/intel/dmar.c:2046 RCU-list traversed in non-reader section!!\n other info that might help us debug this:\n rcu_scheduler_active = 1, debug_locks = 1\n 2 locks held by cpuhp/1/23:\n #0: ffffffff84a67c50 (cpu_hotplug_lock){++++}-{0:0}, at: cpuhp_thread_fun+0x87/0x2c0\n #1: ffffffff84a6a380 (cpuhp_state-up){+.+.}-{0:0}, at: cpuhp_thread_fun+0x87/0x2c0\n stack backtrace:\n CPU: 1 UID: 0 PID: 23 Comm: cpuhp/1 Not tainted 6.14.0-rc3 #55\n Call Trace:\n <TASK>\n dump_stack_lvl+0xb7/0xd0\n lockdep_rcu_suspicious+0x159/0x1f0\n ? __pfx_enable_drhd_fault_handling+0x10/0x10\n enable_drhd_fault_handling+0x151/0x180\n cpuhp_invoke_callback+0x1df/0x990\n cpuhp_thread_fun+0x1ea/0x2c0\n smpboot_thread_fn+0x1f5/0x2e0\n ? __pfx_smpboot_thread_fn+0x10/0x10\n kthread+0x12a/0x2d0\n ? __pfx_kthread+0x10/0x10\n ret_from_fork+0x4a/0x60\n ? __pfx_kthread+0x10/0x10\n ret_from_fork_asm+0x1a/0x30\n </TASK>\n\nHolding the lock in enable_drhd_fault_handling() triggers a lockdep splat\nabout a possible deadlock between dmar_global_lock and cpu_hotplug_lock.\nThis is avoided by not holding dmar_global_lock when calling\niommu_device_register(), which initiates the device probe process."}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.12.18", "versionStartIncluding": "6.10"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.13.6", "versionStartIncluding": "6.10"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.14", "versionStartIncluding": "6.10"}], "operator": "OR"}]}], "providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T11:55:03.667Z"}}}, "cveMetadata": {"cveId": "CVE-2025-21876", "state": "PUBLISHED", "dateUpdated": "2026-10-15T21:51:54.560Z", "dateReserved": "2024-12-29T08:45:45.781Z", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "datePublished": "2025-03-27T14:57:06.802Z", "assignerShortName": "Linux"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["drivers/iommu/intel/dmar.c", "drivers/iommu/intel/iommu.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "4117c72938493a77ab53cc4b8284be8fb6ec8065", "status": "affected", "version": "d74169ceb0d2e32438946a2f1f9fc8c803304bd6", "versionType": "git"}, {"lessThan": "c603ccbe91d189849e1439134598ec567088dcec", "status": "affected", "version": "d74169ceb0d2e32438946a2f1f9fc8c803304bd6", "versionType": "git"}, {"lessThan": "b150654f74bf0df8e6a7936d5ec51400d9ec06d8", "status": "affected", "version": "d74169ceb0d2e32438946a2f1f9fc8c803304bd6", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["drivers/iommu/intel/dmar.c", "drivers/iommu/intel/iommu.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "6.10"}, {"lessThan": "6.10", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.18", "versionType": "semver"}, {"lessThanOrEqual": "6.13.*", "status": "unaffected", "version": "6.13.6", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "6.14", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "C3E726AB-924C-4BAA-9AD5-2EA4A154FEE8", "versionEndExcluding": "6.12.18", "versionStartIncluding": "6.10", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "64F12D9B-71C2-4CD7-A288-0D5EF1709620", "versionEndExcluding": "6.13.6", "versionStartIncluding": "6.13", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:*", "matchCriteriaId": "186716B6-2B66-4BD0-852E-D48E71C0C85F", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:*", "matchCriteriaId": "0D3E781C-403A-498F-9DA9-ECEE50F41E75", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.14:rc3:*:*:*:*:*:*", "matchCriteriaId": "66619FB8-0AAF-4166-B2CF-67B24143261D", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.14:rc4:*:*:*:*:*:*", "matchCriteriaId": "D3D6550E-6679-4560-902D-AF52DCFE905B", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\niommu/vt-d: Fix suspicious RCU usage\n\nCommit <d74169ceb0d2> (\"iommu/vt-d: Allocate DMAR fault interrupts\nlocally\") moved the call to enable_drhd_fault_handling() to a code\npath that does not hold any lock while traversing the drhd list. Fix\nit by ensuring the dmar_global_lock lock is held when traversing the\ndrhd list.\n\nWithout this fix, the following warning is triggered:\n =============================\n WARNING: suspicious RCU usage\n 6.14.0-rc3 #55 Not tainted\n -----------------------------\n drivers/iommu/intel/dmar.c:2046 RCU-list traversed in non-reader section!!\n other info that might help us debug this:\n rcu_scheduler_active = 1, debug_locks = 1\n 2 locks held by cpuhp/1/23:\n #0: ffffffff84a67c50 (cpu_hotplug_lock){++++}-{0:0}, at: cpuhp_thread_fun+0x87/0x2c0\n #1: ffffffff84a6a380 (cpuhp_state-up){+.+.}-{0:0}, at: cpuhp_thread_fun+0x87/0x2c0\n stack backtrace:\n CPU: 1 UID: 0 PID: 23 Comm: cpuhp/1 Not tainted 6.14.0-rc3 #55\n Call Trace:\n <TASK>\n dump_stack_lvl+0xb7/0xd0\n lockdep_rcu_suspicious+0x159/0x1f0\n ? __pfx_enable_drhd_fault_handling+0x10/0x10\n enable_drhd_fault_handling+0x151/0x180\n cpuhp_invoke_callback+0x1df/0x990\n cpuhp_thread_fun+0x1ea/0x2c0\n smpboot_thread_fn+0x1f5/0x2e0\n ? __pfx_smpboot_thread_fn+0x10/0x10\n kthread+0x12a/0x2d0\n ? __pfx_kthread+0x10/0x10\n ret_from_fork+0x4a/0x60\n ? __pfx_kthread+0x10/0x10\n ret_from_fork_asm+0x1a/0x30\n </TASK>\n\nHolding the lock in enable_drhd_fault_handling() triggers a lockdep splat\nabout a possible deadlock between dmar_global_lock and cpu_hotplug_lock.\nThis is avoided by not holding dmar_global_lock when calling\niommu_device_register(), which initiates the device probe process."}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: iommu/vt-d: Correcci\u00f3n de uso sospechoso de RCU. El commit (\"iommu/vt-d: Asignar interrupciones de fallo DMAR localmente\") movi\u00f3 la llamada a enable_drhd_fault_handling() a una ruta de c\u00f3digo que no mantiene ning\u00fan bloqueo al recorrer la lista drhd. Corr\u00edjala asegur\u00e1ndose de que el bloqueo dmar_global_lock se mantenga al recorrer la lista drhd. Sin esta correcci\u00f3n, se activa la siguiente advertencia: ============================= ADVERTENCIA: uso sospechoso de RCU 6.14.0-rc3 #55 No contaminado ----------------------------- drivers/iommu/intel/dmar.c:2046 \u00a1Lista de RCU recorrida en una secci\u00f3n que no es de lectura! Otra informaci\u00f3n que podr\u00eda ayudarnos a depurar esto: rcu_scheduler_active = 1, debug_locks = 1 2 bloqueos mantenidos por cpuhp/1/23: #0: ffffffff84a67c50 (cpu_hotplug_lock){++++}-{0:0}, en: cpuhp_thread_fun+0x87/0x2c0 #1: ffffffff84a6a380 (cpuhp_state-up){+.+.}-{0:0}, en: cpuhp_thread_fun+0x87/0x2c0 seguimiento de pila: CPU: 1 UID: 0 PID: 23 Comm: cpuhp/1 No contaminado 6.14.0-rc3 #55 Seguimiento de llamadas: dump_stack_lvl+0xb7/0xd0 lockdep_rcu_suspicious+0x159/0x1f0 ? __pfx_enable_drhd_fault_handling+0x10/0x10 enable_drhd_fault_handling+0x151/0x180 cpuhp_invoke_callback+0x1df/0x990 cpuhp_thread_fun+0x1ea/0x2c0 smpboot_thread_fn+0x1f5/0x2e0 ? __pfx_smpboot_thread_fn+0x10/0x10 kthread+0x12a/0x2d0 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x4a/0x60 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 Mantener el bloqueo en enable_drhd_fault_handling() activa un aviso de bloqueo sobre un posible interbloqueo entre dmar_global_lock y cpu_hotplug_lock. Esto se evita al no mantener dmar_global_lock al llamar a iommu_device_register(), que inicia el proceso de sondeo del dispositivo."}], "id": "CVE-2025-21876", "lastModified": "2026-10-15T22:18:10.747", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 8.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "CHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 2.0, "impactScore": 6.0, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}, {"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 5.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 3.6, "source": "nvd@nist.gov", "type": "Primary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2025-21876", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2026-10-15T21:43:25.342939Z", "version": "2.0.3"}}]}, "published": "2025-03-27T15:15:55.430", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/4117c72938493a77ab53cc4b8284be8fb6ec8065"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/b150654f74bf0df8e6a7936d5ec51400d9ec06d8"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/c603ccbe91d189849e1439134598ec567088dcec"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "NVD-CWE-noinfo"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"bugzilla": {"description": "kernel: iommu/vt-d: Fix suspicious RCU usage", "id": "2355411", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2355411"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.5", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "details": ["In the Linux kernel, the following vulnerability has been resolved:\niommu/vt-d: Fix suspicious RCU usage\nCommit <d74169ceb0d2> (\"iommu/vt-d: Allocate DMAR fault interrupts\nlocally\") moved the call to enable_drhd_fault_handling() to a code\npath that does not hold any lock while traversing the drhd list. Fix\nit by ensuring the dmar_global_lock lock is held when traversing the\ndrhd list.\nWithout this fix, the following warning is triggered:\n=============================\nWARNING: suspicious RCU usage\n6.14.0-rc3 #55 Not tainted\n-----------------------------\ndrivers/iommu/intel/dmar.c:2046 RCU-list traversed in non-reader section!!\nother info that might help us debug this:\nrcu_scheduler_active = 1, debug_locks = 1\n2 locks held by cpuhp/1/23:\n#0: ffffffff84a67c50 (cpu_hotplug_lock){++++}-{0:0}, at: cpuhp_thread_fun+0x87/0x2c0\n#1: ffffffff84a6a380 (cpuhp_state-up){+.+.}-{0:0}, at: cpuhp_thread_fun+0x87/0x2c0\nstack backtrace:\nCPU: 1 UID: 0 PID: 23 Comm: cpuhp/1 Not tainted 6.14.0-rc3 #55\nCall Trace:\n<TASK>\ndump_stack_lvl+0xb7/0xd0\nlockdep_rcu_suspicious+0x159/0x1f0\n? __pfx_enable_drhd_fault_handling+0x10/0x10\nenable_drhd_fault_handling+0x151/0x180\ncpuhp_invoke_callback+0x1df/0x990\ncpuhp_thread_fun+0x1ea/0x2c0\nsmpboot_thread_fn+0x1f5/0x2e0\n? __pfx_smpboot_thread_fn+0x10/0x10\nkthread+0x12a/0x2d0\n? __pfx_kthread+0x10/0x10\nret_from_fork+0x4a/0x60\n? __pfx_kthread+0x10/0x10\nret_from_fork_asm+0x1a/0x30\n</TASK>\nHolding the lock in enable_drhd_fault_handling() triggers a lockdep splat\nabout a possible deadlock between dmar_global_lock and cpu_hotplug_lock.\nThis is avoided by not holding dmar_global_lock when calling\niommu_device_register(), which initiates the device probe process."], "name": "CVE-2025-21876", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"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": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "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": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2025-03-27T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2025-21876\nhttps://nvd.nist.gov/vuln/detail/CVE-2025-21876\nhttps://lore.kernel.org/linux-cve-announce/2025032710-CVE-2025-21876-6c2f@gregkh/T"], "threat_severity": "Low"}

{}