{"cve":"CVE-2026-68174","nvd":{"published":"2026-08-10T13:20:04.213","modified":"2026-08-17T05:18:18.927","status":"Received","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.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/43a23dfe0024afd3d2b0232e987d0292919a9b24","https://git.kernel.org/stable/c/b4eb07bde606c2096b24252be589e735eff6d413","https://git.kernel.org/stable/c/b6a4575f22925da7e6aa00171e9fc0e5029c0bc9"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:47:54.990491175+00:00"},"epss":{"cve":"CVE-2026-68174","score":0.00198,"percentile":0.0962,"date":"2026-11-01"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}