CVE-2026-103435

Published: Ott 07, 2026 Last Modified: Ott 07, 2026
ExploitDB:
Other exploit source:
Google Dorks:
HIGH 7,7
Source: 98a01053-8a31-4f6d-9aa9-252be161adc6
Attack Vector: network
Attack Complexity: low
Privileges Required: none
User Interaction: passive
Confidentiality: N/A
Integrity: N/A
Availability: N/A

Description

AI Translation Available

Claude Code validated that a target file path resided within the project working directory at permission-check time, but re-resolved the path at write time without repeating that validation. This time-of-check to time-of-use (TOCTOU) gap allowed an attacker who could write to the workspace to atomically replace a project file with a symlink, causing Claude Code to follow the symlink and write its output to an arbitrary file outside the project sandbox. Exploitation required the ability to win a race condition against the write operation and write access to the shared workspace, enabling a lower-privileged attacker to redirect benign edits to sensitive files (e.g., shell configuration) in a higher-privileged session.

Users on standard Claude Code auto-update have received this fix already. Users performing manual updates are advised to update to the latest version.

Thank you to hackerone.com/c_h4ck_0 for reporting this issue.

22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

Stable
Abstraction: Base Structure: Simple
Common Consequences
Security Scopes Affected:
Integrity Confidentiality Availability
Potential Impacts:
Execute Unauthorized Code Or Commands Modify Files Or Directories Read Files Or Directories Dos: Crash, Exit, Or Restart
Applicable Platforms
Technologies: AI/ML
Likelihood of Exploit: High
View CWE Details
61

UNIX Symbolic Link (Symlink) Following

Incomplete
Abstraction: Compound Structure: Composite
Common Consequences
Security Scopes Affected:
Confidentiality Integrity
Potential Impacts:
Read Files Or Directories Modify Files Or Directories
Applicable Platforms
All platforms may be affected
Likelihood of Exploit: High
View CWE Details
367

Time-of-check Time-of-use (TOCTOU) Race Condition

Incomplete
Abstraction: Base Structure: Simple
Common Consequences
Security Scopes Affected:
Integrity Other Non-Repudiation
Potential Impacts:
Alter Execution Logic Unexpected State Modify Application Data Modify Files Or Directories Modify Memory Other Hide Activities
Applicable Platforms
All platforms may be affected
Likelihood of Exploit: Medium
View CWE Details
https://github.com/anthropics/claude-code/security/advisori…
https://github.com/anthropics/claude-code/security/advisories/GHSA-5j29-h97v-84…