An issue was discovered in disable_priv_mode in shell.c in GNU Bash through 5.0 patch 11. By default if Bash is run with its effective UID not equal to its real UID it will drop privileges by setting its effective UID to its real UID. However it does so incorrectly. On Linux and other systems that support "saved UID" functionality the saved UID is not dropped. An attacker with command execution in the shell can use "enable -f" for runtime loading of a new builtin which can be a shared object that calls setuid() and therefore regains privileges. However binaries running with an effective UID of 0 are unaffected.

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DEBIAN-CVE-2019-12522

An issue was discovered in Squid through 4.7. When Squid is run as root, it spawns its child processes as a lesser user, by default the user nobody. This is done via the leavesuid call. leavesuid leaves the Saved UID as 0. This makes it trivial for an attacker who has compromised the child proces...

UBUNTU-CVE-2019-12522

An issue was discovered in Squid through 4.7. When Squid is run as root, it spawns its child processes as a lesser user, by default the user nobody. This is done via the leavesuid call. leavesuid leaves the Saved UID as 0. This makes it trivial for an attacker who has compromised the child proces...

UBUNTU-CVE-2019-18276

An issue was discovered in disableprivmode in shell.c in GNU Bash through 5.0 patch 11. By default, if Bash is run with its effective UID not equal to its real UID, it will drop privileges by setting its effective UID to its real UID. However, it does so incorrectly. On Linux and other systems th...