CVE-2026-74633

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-74633", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-15T05:44:03.922Z", "datePublished": "2026-08-22T15:32:13.808Z", "dateUpdated": "2026-08-22T15:32:13.808Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-22T15:32:13.808Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ntracing: Fix NULL pointer dereference in module event cache removal\n\nA module-only event filter such as \":mod:foo\" is cached with a NULL\nevent_mod->match when foo has not been loaded. If a later write tries to\nremove a specific match from the same module, remove_cache_mod() passes\nthe NULL cached match to strcmp(), causing a NULL pointer dereference.\n\nThe issue can be reproduced from userspace:\n\n echo ':mod:trace_events_kunit_missing' > /sys/kernel/tracing/set_event\n echo '!foo_bar:mod:trace_events_kunit_missing' >> /sys/kernel/tracing/set_event\n\nThe second write must be a concatenation (\">>\") to not include O_TRUNC as\nthat would cause ftrace_clear_events() to clear the cached modules lines.\n\nThe crash was reproduced on x86_64 QEMU while KUnit workers contended on\nthe event tracing path:\n\n BUG: kernel NULL pointer dereference, address: 0000000000000000\n #PF: supervisor read access in kernel mode\n RIP: 0010:strcmp+0x10/0x30\n Call Trace:\n __ftrace_set_clr_event_nolock+0x373/0x4a0\n ftrace_set_clr_event+0xf0/0x180\n ftrace_event_write+0xdf/0x110\n vfs_write+0xf6/0x440\n ksys_write+0x68/0xe0\n do_syscall_64+0xf9/0x540\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\n\nCheck event_mod->match before comparing it, consistent with the existing\nNULL checks for the cached system and event fields. The mismatched removal\ncontinues to return -EINVAL; a broad cached module filter is removed with\n\"!:mod:<module>\"."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["kernel/trace/trace_events.c"], "versions": [{"version": "b355247df104ef6644288884afd2c08b7bf49897", "lessThan": "152a00440dc6ef62c6e4cf9bd881a7e6bb81fda9", "status": "affected", "versionType": "git"}, {"version": "b355247df104ef6644288884afd2c08b7bf49897", "lessThan": "ad4e9dd5fec7a322a471ff36fb9c76214e3c6992", "status": "affected", "versionType": "git"}, {"version": "b355247df104ef6644288884afd2c08b7bf49897", "lessThan": "b69859204d4db3acd86c1c2dadcef0d77b451933", "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/trace/trace_events.c"], "versions": [{"version": "6.14", "status": "affected"}, {"version": "0", "lessThan": "6.14", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.45", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.1.9", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2", "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": "6.14", "versionEndExcluding": "6.18.45"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.14", "versionEndExcluding": "7.1.9"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.14", "versionEndExcluding": "7.2"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/152a00440dc6ef62c6e4cf9bd881a7e6bb81fda9"}, {"url": "https://git.kernel.org/stable/c/ad4e9dd5fec7a322a471ff36fb9c76214e3c6992"}, {"url": "https://git.kernel.org/stable/c/b69859204d4db3acd86c1c2dadcef0d77b451933"}], "title": "tracing: Fix NULL pointer dereference in module event cache removal", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["kernel/trace/trace_events.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "152a00440dc6ef62c6e4cf9bd881a7e6bb81fda9", "status": "affected", "version": "b355247df104ef6644288884afd2c08b7bf49897", "versionType": "git"}, {"lessThan": "ad4e9dd5fec7a322a471ff36fb9c76214e3c6992", "status": "affected", "version": "b355247df104ef6644288884afd2c08b7bf49897", "versionType": "git"}, {"lessThan": "b69859204d4db3acd86c1c2dadcef0d77b451933", "status": "affected", "version": "b355247df104ef6644288884afd2c08b7bf49897", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["kernel/trace/trace_events.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "6.14"}, {"lessThan": "6.14", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.45", "versionType": "semver"}, {"lessThanOrEqual": "7.1.*", "status": "unaffected", "version": "7.1.9", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.2", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ntracing: Fix NULL pointer dereference in module event cache removal\n\nA module-only event filter such as \":mod:foo\" is cached with a NULL\nevent_mod->match when foo has not been loaded. If a later write tries to\nremove a specific match from the same module, remove_cache_mod() passes\nthe NULL cached match to strcmp(), causing a NULL pointer dereference.\n\nThe issue can be reproduced from userspace:\n\n echo ':mod:trace_events_kunit_missing' > /sys/kernel/tracing/set_event\n echo '!foo_bar:mod:trace_events_kunit_missing' >> /sys/kernel/tracing/set_event\n\nThe second write must be a concatenation (\">>\") to not include O_TRUNC as\nthat would cause ftrace_clear_events() to clear the cached modules lines.\n\nThe crash was reproduced on x86_64 QEMU while KUnit workers contended on\nthe event tracing path:\n\n BUG: kernel NULL pointer dereference, address: 0000000000000000\n #PF: supervisor read access in kernel mode\n RIP: 0010:strcmp+0x10/0x30\n Call Trace:\n __ftrace_set_clr_event_nolock+0x373/0x4a0\n ftrace_set_clr_event+0xf0/0x180\n ftrace_event_write+0xdf/0x110\n vfs_write+0xf6/0x440\n ksys_write+0x68/0xe0\n do_syscall_64+0xf9/0x540\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\n\nCheck event_mod->match before comparing it, consistent with the existing\nNULL checks for the cached system and event fields. The mismatched removal\ncontinues to return -EINVAL; a broad cached module filter is removed with\n\"!:mod:<module>\"."}, {"lang": "es", "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\ntracing: Correcci\u00f3n de desreferencia de puntero NULL en la eliminaci\u00f3n de la cach\u00e9 de eventos de m\u00f3dulo\n\nUn filtro de eventos solo de m\u00f3dulo como ':mod:foo' se almacena en cach\u00e9 con un event_mod -> match NULL cuando foo no ha sido cargado. Si una escritura posterior intenta eliminar una coincidencia espec\u00edfica del mismo m\u00f3dulo, remove_cache_mod() pasa la coincidencia NULL almacenada en cach\u00e9 a strcmp(), causando una desreferencia de puntero NULL.\n\nEl problema puede reproducirse desde userspace:\n\n echo ':mod:trace_events_kunit_missing' > /sys/kernel/tracing/set_event\n echo '!foo_bar:mod:trace_events_kunit_missing' >> /sys/kernel/tracing/set_event\n\nLa segunda escritura debe ser una concatenaci\u00f3n ('>>') para no incluir O_TRUNC, ya que eso har\u00eda que ftrace_clear_events() borrara las l\u00edneas de m\u00f3dulos en cach\u00e9.\n\nEl fallo se reprodujo en x86_64 QEMU mientras los workers de KUnit compet\u00edan en la ruta de rastreo de eventos:\n\n BUG: desreferencia de puntero NULL del kernel, direcci\u00f3n: 0000000000000000\n #PF: acceso de lectura de supervisor en modo kernel\n RIP: 0010:strcmp+0x10/0x30\n Traza de Llamada:\n __ftrace_set_clr_event_nolock+0x373/0x4a0\n ftrace_set_clr_event+0xf0/0x180\n ftrace_event_write+0xdf/0x110\n vfs_write+0xf6/0x440\n ksys_write+0x68/0xe0\n do_syscall_64+0xf9/0x540\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\n\nVerificar event_mod -> match antes de compararlo, consistente con las comprobaciones NULL existentes para los campos de sistema y evento en cach\u00e9. La eliminaci\u00f3n no coincidente contin\u00faa devolviendo -EINVAL; un filtro de m\u00f3dulo en cach\u00e9 amplio se elimina con '!:mod:<module>'."}], "id": "CVE-2026-74633", "lastModified": "2026-10-14T13:10:00.187", "metrics": {}, "published": "2026-08-22T16:16:36.380", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/152a00440dc6ef62c6e4cf9bd881a7e6bb81fda9"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/ad4e9dd5fec7a322a471ff36fb9c76214e3c6992"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/b69859204d4db3acd86c1c2dadcef0d77b451933"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: tracing: Fix NULL pointer dereference in module event cache removal", "id": "2521465", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2521465"}, "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"}, "cwe": "CWE-476", "details": ["In the Linux kernel, the following vulnerability has been resolved:\ntracing: Fix NULL pointer dereference in module event cache removal\nA module-only event filter such as \":mod:foo\" is cached with a NULL\nevent_mod->match when foo has not been loaded. If a later write tries to\nremove a specific match from the same module, remove_cache_mod() passes\nthe NULL cached match to strcmp(), causing a NULL pointer dereference.\nThe issue can be reproduced from userspace:\necho ':mod:trace_events_kunit_missing' > /sys/kernel/tracing/set_event\necho '!foo_bar:mod:trace_events_kunit_missing' >> /sys/kernel/tracing/set_event\nThe second write must be a concatenation (\">>\") to not include O_TRUNC as\nthat would cause ftrace_clear_events() to clear the cached modules lines.\nThe crash was reproduced on x86_64 QEMU while KUnit workers contended on\nthe event tracing path:\nBUG: kernel NULL pointer dereference, address: 0000000000000000\n#PF: supervisor read access in kernel mode\nRIP: 0010:strcmp+0x10/0x30\nCall Trace:\n__ftrace_set_clr_event_nolock+0x373/0x4a0\nftrace_set_clr_event+0xf0/0x180\nftrace_event_write+0xdf/0x110\nvfs_write+0xf6/0x440\nksys_write+0x68/0xe0\ndo_syscall_64+0xf9/0x540\nentry_SYSCALL_64_after_hwframe+0x77/0x7f\nCheck event_mod->match before comparing it, consistent with the existing\nNULL checks for the cached system and event fields. The mismatched removal\ncontinues to return -EINVAL; a broad cached module filter is removed with\n\"!:mod:<module>\".", "A flaw was found in the Linux kernel's tracing module. A local user can trigger a NULL pointer dereference by attempting to remove a specific event filter for an unloaded module. This vulnerability arises when a module-only event filter is cached with a null match, and a subsequent write operation passes this null value to a string comparison function. Successful exploitation leads to a system crash, resulting in a Denial of Service (DoS)."], "name": "CVE-2026-74633", "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": "Out of support scope", "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": "2026-08-22T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-74633\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-74633\nhttps://lore.kernel.org/linux-cve-announce/2026082222-CVE-2026-74633-6b87@gregkh/T"], "threat_severity": "Low"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[b355247df104ef6644288884afd2c08b7bf49897,152a00440dc6ef62c6e4cf9bd881a7e6bb81fda9)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[b355247df104ef6644288884afd2c08b7bf49897,ad4e9dd5fec7a322a471ff36fb9c76214e3c6992)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[b355247df104ef6644288884afd2c08b7bf49897,b69859204d4db3acd86c1c2dadcef0d77b451933)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "6.14"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,6.14)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[6.18.45,6.18.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.1.9,7.1.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.2,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-08-22T18:45:04.540985+00:00", "updated": "2026-08-25T13:45:04.367079+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}