CVE-2021-45444
zsh: Prompt expansion vulnerability
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · February 12, 2022
Updated · November 22, 2025
Description
A vulnerability was found in zsh in the parsecolorchar() function of prompt.c file. This flaw allows an attacker to perform code execution if they control a command output inside the prompt, as stated by a %F%K argument. This occurs because of recursive PROMPT_SUBST expansion.
Statement
Red Hat Enterprise Linux 6 and 7 are not affected, because the vulnerable function is not present in the code-base.
Red Hat Product Security has rated this issue as having a Moderate security impact, and the issue is not currently planned to be addressed in future updates for Red Hat Enterprise Linux 6 and 7, hence, marked as Out-of-Support-Scope.
For additional information, refer to the Issue Severity Classification: https://access.redhat.com/security/updates/classification/ and Red Hat Enterprise Linux Life Cycle & Updates Policy: https://access.redhat.com/support/policy/updates/errata/.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.1 · 7.8CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CWE-77 · Improper Neutralization of Special Elements used in a Command ('Command Injection')