{"cve":"CVE-2026-80778","nvd":{"published":"2026-09-04T16:18:03.490","modified":"2026-10-19T09:17:11.900","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nfutex/pi: Reject cross-mm private futex owners\n\nA private futex key borrows the waiter's mm without taking an mm_users\nreference. Nevertheless, attach_to_pi_owner() currently accepts an owner\nfrom a different address space and copies the private key into the owner's\nPI state.\n\nWhen that owner exits, exit_pi_state_list() uses the saved key to find the\nhash bucket and acquires a reference to the waiter's private hash. If the\nlast user of the waiter's mm exits concurrently, futex_hash_free() frees\nthe hash while the owner still uses its bucket and reference.\n\nPrevent this by validating in attach_to_pi_owner() that, for private\nfutexes, the owner mm and waiter mm are the same. Perform the check with\nthe owner's pi_lock held and after validating owner::futex::state to\nserialize against a concurrent PI-state exit cleanup.\n\n[ tglx: Amended comment ]","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/2b92e5562653b5293529f63b0300837d9dcedbd7","https://git.kernel.org/stable/c/43b148d796aa338858792d0167cebdc12b8cb4b9","https://git.kernel.org/stable/c/59b3732f95dda1fbd2234514d35f4fb6b5bb6d85","https://git.kernel.org/stable/c/f7fb3e07752688842cbe0b85cf0d98c2fbf76b68"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:52:03.409947763+00:00"},"epss":{"cve":"CVE-2026-80778","score":0.00168,"percentile":0.06031,"date":"2026-10-25"},"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."]}