OS Command Injection in Claude Code - CVE-2026-25723

 

OS Command Injection in Claude Code - CVE-2026-25723

Published: April 30, 2026


Vulnerability identifier: #VU128513
CSH Severity: High
CVSSv4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber
CVE-ID: CVE-2026-25723
CWE-ID: CWE-78
Exploitation vector: Remote access
Exploit availability: No public exploit available
Vulnerable software:
Claude Code
Software vendor:
Anthropic

Description

The vulnerability allows a remote attacker to execute arbitrary commands and write files outside intended restrictions.

The vulnerability exists due to command injection in the piped sed command handling in Claude Code when processing commands that use piped sed operations with the echo command. A remote attacker can send a specially crafted command to execute arbitrary commands and write files outside intended restrictions.

Exploitation requires the ability to execute commands through Claude Code with the "accept edits" feature enabled.


Remediation

Install security update from vendor's website.

External links