Всем привет!Совсем недавно в ядре линукс была обнаружена критичная уязвимость, позволяющая повышать привилегии до уровня root. Она получила идентификатор CVE-2023-0386 и затронула версии ядра до 6.2. В интернете уже есть несколько доступных PoC: https://github.com/CKevens/CVE-2023-0386 https://github.com/xkaneiki/CVE-2023-0386В этой статье я хотел рассмотреть принцип работы данной уязвимости и возможные варианты ее обнаружения. Читать далее
A vulnerability was found in Linux kernel's, versions up to 3.10, implementation of overlayfs. An attacker with local access can create a denial of service situation via NULL pointer dereference in ovl_posix_acl_create function in fs/overlayfs/dir.c. This can allow attackers with ability to create directories on overlayfs to crash the kernel creating a denial of service (DOS).
A security issue was found in Linux kernel’s OverlayFS subsystem where a local attacker who has the ability to mount the TmpFS filesystem with OverlayFS can abuse a logic bug in the overlayfs code which can inadvertently reveal files hidden in the original mount.
A flaw was found in the Linux kernel, where unauthorized access to the execution of the setuid file with capabilities was found in the Linux kernel’s OverlayFS subsystem in how a user copies a capable file from a nosuid mount into another mount. This uid mapping bug allows a local user to escalate their privileges on the system.