CVE Database›Document archive›CVE-2021-45444

CVE-2021-45444

zsh: Prompt expansion vulnerability

Loading…

Severity

Moderate

Red Hat Product Security

7.8

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 · 7.8
CVSS: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')