Arch Linux Security Advisory ASA-202102-26 ========================================== Severity: High Date : 2021-02-12 CVE-ID : CVE-2021-26910 Package : firejail Type : privilege escalation Remote : No Link : https://security.archlinux.org/AVG-1545 Summary ======= The package firejail before version 0.9.64.4-1 is vulnerable to privilege escalation. Resolution ========== Upgrade to 0.9.64.4-1. # pacman -Syu "firejail>=0.9.64.4-1" The problem has been fixed upstream in version 0.9.64.4. Workaround ========== The issue can be mitigated by setting "overlayfs no" in /etc/firejail/firejail.config. Description =========== Firejail before 0.9.64.4 allows attackers to bypass intended access restrictions because there is a TOCTOU race condition between a stat operation and an OverlayFS mount operation. Impact ====== A local unprivileged attacker can obtain arbitrary file system access for an application running within a firejail sandbox, leading to potential privilege escalation. References ========== https://unparalleled.eu/publications/2021/advisory-unpar-2021-0.txt https://unparalleled.eu/blog/2021/20210208-rigged-race-against-firejail-for-... https://github.com/netblue30/firejail/commit/97d8a03cad19501f017587cc4e47d84... https://security.archlinux.org/CVE-2021-26910