CVE-2025-39744

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2025-39744", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-04-16T07:20:57.120Z", "datePublished": "2025-09-11T16:52:17.725Z", "dateUpdated": "2026-10-30T12:22:24.618Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-30T12:22:24.618Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nrcu: Fix rcu_read_unlock() deadloop due to IRQ work\n\nDuring rcu_read_unlock_special(), if this happens during irq_exit(), we\ncan lockup if an IPI is issued. This is because the IPI itself triggers\nthe irq_exit() path causing a recursive lock up.\n\nThis is precisely what Xiongfeng found when invoking a BPF program on\nthe trace_tick_stop() tracepoint As shown in the trace below. Fix by\nmanaging the irq_work state correctly.\n\nirq_exit()\n __irq_exit_rcu()\n /* in_hardirq() returns false after this */\n preempt_count_sub(HARDIRQ_OFFSET)\n tick_irq_exit()\n tick_nohz_irq_exit()\n\t tick_nohz_stop_sched_tick()\n\t trace_tick_stop() /* a bpf prog is hooked on this trace point */\n\t\t __bpf_trace_tick_stop()\n\t\t bpf_trace_run2()\n\t\t\t rcu_read_unlock_special()\n /* will send a IPI to itself */\n\t\t\t irq_work_queue_on(&rdp->defer_qs_iw, rdp->cpu);\n\nA simple reproducer can also be obtained by doing the following in\ntick_irq_exit(). It will hang on boot without the patch:\n\n static inline void tick_irq_exit(void)\n {\n +\trcu_read_lock();\n +\tWRITE_ONCE(current->rcu_read_unlock_special.b.need_qs, true);\n +\trcu_read_unlock();\n +\n\n[neeraj: Apply Frederic's suggested fix for PREEMPT_RT]"}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["kernel/rcu/tree.h", "kernel/rcu/tree_plugin.h"], "versions": [{"version": "0864f057b050bc6dd68106b3185e02db5140012d", "lessThan": "6b552ffd21f9be57806ade167a757f32dd66a98d", "status": "affected", "versionType": "git"}, {"version": "0864f057b050bc6dd68106b3185e02db5140012d", "lessThan": "e7a375453cca2b8a0d2fa1b82b913f3fed7c0507", "status": "affected", "versionType": "git"}, {"version": "0864f057b050bc6dd68106b3185e02db5140012d", "lessThan": "1cfa244f7198d325594e627574930b7b91df5bfe", "status": "affected", "versionType": "git"}, {"version": "0864f057b050bc6dd68106b3185e02db5140012d", "lessThan": "ddebb2a7677673cf4438a04e1a48b8ed6b0c8e9a", "status": "affected", "versionType": "git"}, {"version": "0864f057b050bc6dd68106b3185e02db5140012d", "lessThan": "56c5ef194f4509df63fc0f7a91ea5973ce479b1e", "status": "affected", "versionType": "git"}, {"version": "0864f057b050bc6dd68106b3185e02db5140012d", "lessThan": "b41642c87716bbd09797b1e4ea7d904f06c39b7b", "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/rcu/tree.h", "kernel/rcu/tree_plugin.h"], "versions": [{"version": "5.3", "status": "affected"}, {"version": "0", "lessThan": "5.3", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.191", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.103", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.43", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.15.11", "lessThanOrEqual": "6.15.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.16.2", "lessThanOrEqual": "6.16.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.17", "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": "5.3", "versionEndExcluding": "6.1.191"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "6.6.103"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "6.12.43"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "6.15.11"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "6.16.2"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.3", "versionEndExcluding": "6.17"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/6b552ffd21f9be57806ade167a757f32dd66a98d"}, {"url": "https://git.kernel.org/stable/c/e7a375453cca2b8a0d2fa1b82b913f3fed7c0507"}, {"url": "https://git.kernel.org/stable/c/1cfa244f7198d325594e627574930b7b91df5bfe"}, {"url": "https://git.kernel.org/stable/c/ddebb2a7677673cf4438a04e1a48b8ed6b0c8e9a"}, {"url": "https://git.kernel.org/stable/c/56c5ef194f4509df63fc0f7a91ea5973ce479b1e"}, {"url": "https://git.kernel.org/stable/c/b41642c87716bbd09797b1e4ea7d904f06c39b7b"}], "title": "rcu: Fix rcu_read_unlock() deadloop due to IRQ work", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["kernel/rcu/tree.h", "kernel/rcu/tree_plugin.h"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "6b552ffd21f9be57806ade167a757f32dd66a98d", "status": "affected", "version": "0864f057b050bc6dd68106b3185e02db5140012d", "versionType": "git"}, {"lessThan": "e7a375453cca2b8a0d2fa1b82b913f3fed7c0507", "status": "affected", "version": "0864f057b050bc6dd68106b3185e02db5140012d", "versionType": "git"}, {"lessThan": "1cfa244f7198d325594e627574930b7b91df5bfe", "status": "affected", "version": "0864f057b050bc6dd68106b3185e02db5140012d", "versionType": "git"}, {"lessThan": "ddebb2a7677673cf4438a04e1a48b8ed6b0c8e9a", "status": "affected", "version": "0864f057b050bc6dd68106b3185e02db5140012d", "versionType": "git"}, {"lessThan": "56c5ef194f4509df63fc0f7a91ea5973ce479b1e", "status": "affected", "version": "0864f057b050bc6dd68106b3185e02db5140012d", "versionType": "git"}, {"lessThan": "b41642c87716bbd09797b1e4ea7d904f06c39b7b", "status": "affected", "version": "0864f057b050bc6dd68106b3185e02db5140012d", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["kernel/rcu/tree.h", "kernel/rcu/tree_plugin.h"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "5.3"}, {"lessThan": "5.3", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.191", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.103", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.43", "versionType": "semver"}, {"lessThanOrEqual": "6.15.*", "status": "unaffected", "version": "6.15.11", "versionType": "semver"}, {"lessThanOrEqual": "6.16.*", "status": "unaffected", "version": "6.16.2", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "6.17", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "AC0A252C-F6BD-41C1-A461-AD2D5B2E915E", "versionEndExcluding": "6.6.103", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "472C5F87-2BF3-4FAB-9B21-DA7513977363", "versionEndExcluding": "6.12.43", "versionStartIncluding": "6.7", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "BC242347-F722-43AE-B910-BE0B22386977", "versionEndExcluding": "6.15.11", "versionStartIncluding": "6.13", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "BD7C087D-2415-4521-B624-30003352F899", "versionEndExcluding": "6.16.2", "versionStartIncluding": "6.16", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nrcu: Fix rcu_read_unlock() deadloop due to IRQ work\n\nDuring rcu_read_unlock_special(), if this happens during irq_exit(), we\ncan lockup if an IPI is issued. This is because the IPI itself triggers\nthe irq_exit() path causing a recursive lock up.\n\nThis is precisely what Xiongfeng found when invoking a BPF program on\nthe trace_tick_stop() tracepoint As shown in the trace below. Fix by\nmanaging the irq_work state correctly.\n\nirq_exit()\n __irq_exit_rcu()\n /* in_hardirq() returns false after this */\n preempt_count_sub(HARDIRQ_OFFSET)\n tick_irq_exit()\n tick_nohz_irq_exit()\n\t tick_nohz_stop_sched_tick()\n\t trace_tick_stop() /* a bpf prog is hooked on this trace point */\n\t\t __bpf_trace_tick_stop()\n\t\t bpf_trace_run2()\n\t\t\t rcu_read_unlock_special()\n /* will send a IPI to itself */\n\t\t\t irq_work_queue_on(&rdp->defer_qs_iw, rdp->cpu);\n\nA simple reproducer can also be obtained by doing the following in\ntick_irq_exit(). It will hang on boot without the patch:\n\n static inline void tick_irq_exit(void)\n {\n +\trcu_read_lock();\n +\tWRITE_ONCE(current->rcu_read_unlock_special.b.need_qs, true);\n +\trcu_read_unlock();\n +\n\n[neeraj: Apply Frederic's suggested fix for PREEMPT_RT]"}, {"lang": "es", "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nrcu: Correcci\u00f3n del bucle muerto de rcu_read_unlock() debido al trabajo IRQ\n\nDurante rcu_read_unlock_special(), si esto ocurre durante irq_exit(), podemos bloquearnos si se emite un IPI. Esto se debe a que el propio IPI desencadena la ruta de irq_exit() causando un bloqueo recursivo.\n\nEsto es precisamente lo que Xiongfeng encontr\u00f3 al invocar un programa BPF en el punto de rastreo trace_tick_stop(). Como se muestra en el rastreo a continuaci\u00f3n. Se corrige gestionando el estado de irq_work correctamente.\n\nirq_exit()\n __irq_exit_rcu()\n /* in_hardirq() devuelve falso despu\u00e9s de esto */\n preempt_count_sub(HARDIRQ_OFFSET)\n tick_irq_exit()\n tick_nohz_irq_exit()\n\t tick_nohz_stop_sched_tick()\n\t trace_tick_stop() /* un programa bpf est\u00e1 enganchado a este punto de rastreo */\n\t\t __bpf_trace_tick_stop()\n\t\t bpf_trace_run2()\n\t\t\t rcu_read_unlock_special()\n /* enviar\u00e1 un IPI a s\u00ed mismo */\n\t\t\t irq_work_queue_on(&rdp->defer_qs_iw, rdp->cpu);\n\nUn reproductor simple tambi\u00e9n se puede obtener haciendo lo siguiente en tick_irq_exit(). Se colgar\u00e1 al arrancar sin el parche:\n\n static inline void tick_irq_exit(void)\n {\n +\trcu_read_lock();\n +\tWRITE_ONCE(current->rcu_read_unlock_special.b.need_qs, true);\n +\trcu_read_unlock();\n +\n\n[neeraj: Aplicar la correcci\u00f3n sugerida por Frederic para PREEMPT_RT]"}], "id": "CVE-2025-39744", "lastModified": "2026-10-30T13:18:09.093", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.1, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.2, "source": "nvd@nist.gov", "type": "Primary"}]}, "published": "2025-09-11T17:15:37.600", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/1cfa244f7198d325594e627574930b7b91df5bfe"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/56c5ef194f4509df63fc0f7a91ea5973ce479b1e"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/6b552ffd21f9be57806ade167a757f32dd66a98d"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/b41642c87716bbd09797b1e4ea7d904f06c39b7b"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/ddebb2a7677673cf4438a04e1a48b8ed6b0c8e9a"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/e7a375453cca2b8a0d2fa1b82b913f3fed7c0507"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-125"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"bugzilla": {"description": "kernel: rcu: Fix rcu_read_unlock() deadloop due to IRQ work", "id": "2394602", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2394602"}, "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": ["No description is available for this CVE."], "name": "CVE-2025-39744", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not affected", "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": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2025-09-11T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2025-39744\nhttps://nvd.nist.gov/vuln/detail/CVE-2025-39744\nhttps://lore.kernel.org/linux-cve-announce/2025091140-CVE-2025-39744-2744@gregkh/T"], "threat_severity": "Moderate"}

{"created": "2025-09-12T08:02:37.245872+00:00", "updated": "2025-09-12T08:02:37.245934+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}