Two new Linux kernel privilege escalation flaws have been discovered in the OverlayFS module in Ubuntu, which affect nearly 40% of Ubuntu users (CVE-2023-2640 and CVE-2023-32629). Modifications to the OverlayFS module introduced by the Linux kernel project in 2019 and 2022 conflicted with Ubuntu’s earlier changes, and Ubuntu's adoption of the new code introduced these two vulnerabilities. . The researchers who discovered these vulnerabilities have stated, “Both vulnerabilities are unique to Ubuntu kernels since they stemmed from Ubuntu’s individual changes to the OverlayFS module. Weaponized exploits for these vulnerabilities are already publicly available given old exploits for past OverlayFS vulnerabilities work out of the box without any changes.” These issues can allow an unprivileged local user to gain elevated privileges on impacted systems. Important updates for the kernel that mitigate these severe vulnerabilities are now available for Ubuntu users. We strongly recommend that all impacted users apply these updates immediately to protect against privilege escalation attacks leading to system compromise. To stay on top of essential updates released by the open-source programs and applications you use, register as a LinuxSecurity user , subscribe to our Linux Advisory Watch newsletter, and customize your advisories for your distro(s). This will enable you to stay up-to-date on the latest, most significant issues impacting the security of your systems. Follow @LS_Advisories on Twitter for real-time updates on advisories for your distro(s) . . Crucial patches released for Ubuntu systems to address emerging security vulnerabilities in the OverlayFS component.. Ubuntu Kernel Flaws, Privilege Escalation, OverlayFS Issues. . Brittany Day
Redhat has just just published a risk advisory about a vulnerability in the Linux Kernel that allows for local privilege escalation. This vulnerability is tracked as CVE-2022-3910 (CVSS score: 7.4). . This vulnerability is referred to be a use-after-free problem, and it can be found in io uring on the Update of Reference Count. io uring is an interface for making system calls in Linux. It made its debut for the very first time in the mainline Linux Kernel version 5.1 in the year 2019. It gives an application the ability to start system calls that may be carried out in an asynchronous manner. A Use-After-Free vulnerability and a Local Privilege Escalation may be caused in the Linux kernel by incorrectly updating the reference count in the io uring function. When io msg ring is called with a fixed file, it invokes io fput file(), which incorrectly lowers its reference count. Fixed files are those that are permanently registered to the ring and must not be stored in a separate location. . A critical out-of-bounds memory access vulnerability in the Linux Kernel presents a potential risk for local privilege escalation. Immediate attention required.. Local Privilege Escalation, Kernel Patching, Red Hat Security. . Brittany Day
An error in the handling of special netlink messages in the Linux kernel can allow a user to surreptitiously gain root privileges. The discoverer of the hole, Mathais Krause, confirmed to The H's associates at heise Security that Linux kernel versions 3.3 to 3.8 are affected. . These are used by, among other things, Fedora 17, 18 and Ubuntu 12.10. Red Hat and SUSE are unaffected as they have not ported the code in question back to the older kernels their distributions are based on. The link for this article located at H Security is no longer available. . A vulnerability in Linux kernels from versions 3.3 to 3.8 may allow for unauthorized administrative entry. Impacted systems include Fedora and Ubuntu.. Linux Kernel Security, Root Access Vulnerability, Open Source Threats. . LinuxSecurity.com Team
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