CVE-2026-68179
Analyse NVD en cours
In the Linux kernel, the following vulnerability has been resolved: misc: nsm: only unlock nsm_dev on post-lock error paths nsm_dev_ioctl() jumps to the common out label even when the initial copy_from_user() fails before nsm->lock has been taken. The error path then blindly unlocks a mutex that was never acquired. This issue was found by our static analysis tool and then manually reviewed against the current tree. The grounded PoC kept the miscdevice ioctl entry and the pre-lock copy_from_user(&raw, argp, _IOC_SIZE(cmd)) failure path by issuing NSM_IOCTL_RAW with an invalid user pointer. That failure reaches the shared out label before mutex_lock(&nsm->lock). Lockdep reported: WARNING: bad unlock balance detected! exploit/193 is trying to release lock (&global_nsm.lock) at: nsm_dev_ioctl+0x5f/0xcf [vuln_msv] but there are no more locks to release! no locks held by exploit/193. Return immediately on the pre-lock copy_from_user() failure and keep the common unlock label for the post-lock paths only.
Ce que ça veut dire
- Exposition
- Exploitable avec un accès local à la machine, sans authentification et sans action de la victime.
- Impact
- Un attaquant peut lire des données sensibles, modifier ou détruire des données et mettre le service hors ligne.
- Probabilité
- Le score EPSS reste bas : rien n’annonce une exploitation imminente, ce qui ne dispense pas de corriger.
À faireÀ intégrer au prochain cycle de correctifs.
Lecture automatique du vecteur CVSS, du type de faiblesse (CWE) et du score EPSS. La description technique ci-dessus reste celle publiée par le NIST, en anglais.