CVE-2021-3726: OS Command Injection in ohmyzsh/ohmyzsh

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-11-30 · updated 2026-06-17
Weakness: CWE-78

Description

# Vulnerability in `title` function **Description**: the `title` function defined in `lib/termsupport.zsh` uses `print` to set the terminal title to a user-supplied string. In Oh My Zsh, this function is always used securely, but custom user code could use the `title` function in a way that is unsafe. **Fixed in**: [a263cdac](https://github.com/ohmyzsh/ohmyzsh/commit/a263cdac). **Impacted areas**: - `title` function in `lib/termsupport.zsh`. - Custom user code using the `title` function.

Affected products

ohmyzsh/ohmyzsh: before 2021-11-11 — fixed in 2021-11-11

How to fix

Upgrade to a fixed version: ohmyzsh/ohmyzsh 2021-11-11. Check the vendor advisory for mitigations.

References

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