Sequoia: A Local Privilege Escalation Vulnerability in Linux’s Filesystem Layer – . Wheel – PSW #707
The Qualys Research Team discovered a size_t-to-int type conversion vulnerability in the Linux Kernel’s filesystem layer affecting most Linux operating systems. Any unprivileged user can gain root privileges on a vulnerable host by exploiting this vulnerability in a default configuration. Successful exploitation of this vulnerability allows any unprivileged user to gain root privileges on the vulnerable host. Qualys security researchers have been able to independently verify the vulnerability, develop an exploit, and obtain full root privileges on default installations of Ubuntu 20.04, Ubuntu 20.10, Ubuntu 21.04, Debian 11, and Fedora 34 Workstation. Other Linux distributions are likely vulnerable and probably exploitable.
Segment Resources:
https://blog.qualys.com/vulnerabilities-threat-research/2021/07/20/sequoia-a-local-privilege-escalation-vulnerability-in-linuxs-filesystem-layer-cve-2021-33909
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“Wheel” is a member of the Qualys Research Team responsible for finding zero-days.