CVE-2019-18276

Priority
Description
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.
Notes
Package
Source: bash (LP Ubuntu Debian)
Upstream:needs-triage
Ubuntu 12.04 ESM (Precise Pangolin):needed
Ubuntu 14.04 ESM (Trusty Tahr):needed
Ubuntu 16.04 LTS (Xenial Xerus):needed
Ubuntu 18.04 LTS (Bionic Beaver):needed
Ubuntu 19.04 (Disco Dingo):ignored (reached end-of-life)
Ubuntu 19.10 (Eoan Ermine):needed
Ubuntu 20.04 (Focal Fossa):needed
Patches:
Upstream:https://git.savannah.gnu.org/cgit/bash.git/commit/?h=devel&id=951bdaad7a18cc0dc1036bba86b18b90874d39ff
More Information

Updated: 2020-01-23 20:49:17 UTC (commit b4629892d998f2ede31f59bb7508dc50a92ac664)