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.
CVSS Score
7.8
EPSS Score
0.4
Published
2019-11-28
rbash in Bash before 4.4-beta2 did not prevent the shell user from modifying BASH_CMDS, thus allowing the user to execute any command with the permissions of the shell.
CVSS Score
7.8
EPSS Score
0.003
Published
2019-03-22
The path autocompletion feature in Bash 4.4 allows local users to gain privileges via a crafted filename starting with a " (double quote) character and a command substitution metacharacter.
CVSS Score
7.8
EPSS Score
0.002
Published
2017-03-27
popd in bash might allow local users to bypass the restricted shell and cause a use-after-free via a crafted address.
CVSS Score
5.5
EPSS Score
0.0
Published
2017-01-23