{"api_version":"1","generated_at":"2026-08-13T21:33:27+00:00","cve":"CVE-2026-68174","urls":{"html":"https://cve.report/CVE-2026-68174","api":"https://cve.report/api/cve/CVE-2026-68174.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-68174","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-68174"},"summary":{"title":"tracing: Fix union collision of module and refcnt for dynamic events","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ntracing: Fix union collision of module and refcnt for dynamic events\n\nIn 'struct trace_event_call', the 'module' pointer and the 'refcnt'\natomic variable share the same memory space in a union. For dynamic\nevents, the union member is 'refcnt', which acts as an active\nreference counter.\n\nWhen a dynamic event (such as kprobe, uprobe, fprobe, eprobe, or\nwprobe) has a non-zero reference count (e.g. due to active event\ntriggers or perf attachments), its 'call->module' evaluates to a\nsmall non-zero integer instead of NULL.\n\nWhen filtering or setting events for a specific module (e.g., writing\n':mod:<module>' to 'set_event'), the code in\n'__ftrace_set_clr_event_nolock()' and 'update_event_fields()' reads\n'call->module' directly without checking whether the event is dynamic.\nThis causes the kernel to treat the small integer (refcnt) as a\n'struct module' pointer, leading to a NULL/invalid pointer dereference\n(Oops) when dereferencing the module name.\n\nFix this by ensuring that the 'TRACE_EVENT_FL_DYNAMIC' flag is checked\nbefore treating 'call->module' as a valid pointer in these code paths.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-08-10 13:20:04","updated_at":"2026-08-10 13:20:04"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/43a23dfe0024afd3d2b0232e987d0292919a9b24","name":"https://git.kernel.org/stable/c/43a23dfe0024afd3d2b0232e987d0292919a9b24","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/b6a4575f22925da7e6aa00171e9fc0e5029c0bc9","name":"https://git.kernel.org/stable/c/b6a4575f22925da7e6aa00171e9fc0e5029c0bc9","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/b4eb07bde606c2096b24252be589e735eff6d413","name":"https://git.kernel.org/stable/c/b4eb07bde606c2096b24252be589e735eff6d413","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-68174","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-68174","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 4c86bc531e60900053384867c082675bba82c29f b6a4575f22925da7e6aa00171e9fc0e5029c0bc9 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 4c86bc531e60900053384867c082675bba82c29f 43a23dfe0024afd3d2b0232e987d0292919a9b24 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 4c86bc531e60900053384867c082675bba82c29f b4eb07bde606c2096b24252be589e735eff6d413 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.14","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.14 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.42 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1.6 7.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2-rc5 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"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":"b6a4575f22925da7e6aa00171e9fc0e5029c0bc9","status":"affected","version":"4c86bc531e60900053384867c082675bba82c29f","versionType":"git"},{"lessThan":"43a23dfe0024afd3d2b0232e987d0292919a9b24","status":"affected","version":"4c86bc531e60900053384867c082675bba82c29f","versionType":"git"},{"lessThan":"b4eb07bde606c2096b24252be589e735eff6d413","status":"affected","version":"4c86bc531e60900053384867c082675bba82c29f","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":"6.18.42","versionType":"semver"},{"lessThanOrEqual":"7.1.*","status":"unaffected","version":"7.1.6","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.2-rc5","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.42","versionStartIncluding":"6.14","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1.6","versionStartIncluding":"6.14","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2-rc5","versionStartIncluding":"6.14","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ntracing: Fix union collision of module and refcnt for dynamic events\n\nIn 'struct trace_event_call', the 'module' pointer and the 'refcnt'\natomic variable share the same memory space in a union. For dynamic\nevents, the union member is 'refcnt', which acts as an active\nreference counter.\n\nWhen a dynamic event (such as kprobe, uprobe, fprobe, eprobe, or\nwprobe) has a non-zero reference count (e.g. due to active event\ntriggers or perf attachments), its 'call->module' evaluates to a\nsmall non-zero integer instead of NULL.\n\nWhen filtering or setting events for a specific module (e.g., writing\n':mod:<module>' to 'set_event'), the code in\n'__ftrace_set_clr_event_nolock()' and 'update_event_fields()' reads\n'call->module' directly without checking whether the event is dynamic.\nThis causes the kernel to treat the small integer (refcnt) as a\n'struct module' pointer, leading to a NULL/invalid pointer dereference\n(Oops) when dereferencing the module name.\n\nFix this by ensuring that the 'TRACE_EVENT_FL_DYNAMIC' flag is checked\nbefore treating 'call->module' as a valid pointer in these code paths."}],"providerMetadata":{"dateUpdated":"2026-08-10T11:59:44.417Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/b6a4575f22925da7e6aa00171e9fc0e5029c0bc9"},{"url":"https://git.kernel.org/stable/c/43a23dfe0024afd3d2b0232e987d0292919a9b24"},{"url":"https://git.kernel.org/stable/c/b4eb07bde606c2096b24252be589e735eff6d413"}],"title":"tracing: Fix union collision of module and refcnt for dynamic events","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-68174","datePublished":"2026-08-10T11:59:44.417Z","dateReserved":"2026-07-30T09:28:09.372Z","dateUpdated":"2026-08-10T11:59:44.417Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-08-10 13:20:04","lastModifiedDate":"2026-08-10 13:20:04","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"68174","Ordinal":"1","Title":"tracing: Fix union collision of module and refcnt for dynamic ev","CVE":"CVE-2026-68174","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"68174","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\ntracing: Fix union collision of module and refcnt for dynamic events\n\nIn 'struct trace_event_call', the 'module' pointer and the 'refcnt'\natomic variable share the same memory space in a union. For dynamic\nevents, the union member is 'refcnt', which acts as an active\nreference counter.\n\nWhen a dynamic event (such as kprobe, uprobe, fprobe, eprobe, or\nwprobe) has a non-zero reference count (e.g. due to active event\ntriggers or perf attachments), its 'call->module' evaluates to a\nsmall non-zero integer instead of NULL.\n\nWhen filtering or setting events for a specific module (e.g., writing\n':mod:<module>' to 'set_event'), the code in\n'__ftrace_set_clr_event_nolock()' and 'update_event_fields()' reads\n'call->module' directly without checking whether the event is dynamic.\nThis causes the kernel to treat the small integer (refcnt) as a\n'struct module' pointer, leading to a NULL/invalid pointer dereference\n(Oops) when dereferencing the module name.\n\nFix this by ensuring that the 'TRACE_EVENT_FL_DYNAMIC' flag is checked\nbefore treating 'call->module' as a valid pointer in these code paths.","Type":"Description","Title":"tracing: Fix union collision of module and refcnt for dynamic ev"}]}}}