Vulnerability · Published Nov 3, 2026 · Assigned by GitHub_M

CVE-2026-88968Claude Code: TOCTOU Race in Edit Tool Allows File Writes Outside the Workspace

High 7.7

In plain English

A high-severity security flaw in claude-code from anthropics. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 25% of all known vulnerabilities).

Severity (CVSS 4.0)7.7High

Exploit odds (30 days)0.3%top 75.2% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

Claude Code is an agentic coding tool. Prior to 2.1.251, the Edit tool validates a target using pathname and symlink resolution that is not bound to the underlying directory inode or file descriptor. On macOS, attacker-controlled code running in the Bash sandbox can atomically replace an in-workspace parent directory with a symlink after validation, causing the unsandboxed Edit implementation to overwrite a user-writable file outside the workspace. Exploitation requires attacker-controlled code to run inside the sandbox, such as from a malicious repository or dependency script. This issue is fixed in version 2.1.251.

Affected products (as reported)

Vendor	Product	Versions
anthropics	claude-code	< 2.1.251

Weakness: CWE-59, CWE-367 · Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

References

https://github.com/anthropics/claude-code/security/advisories/GHSA-5xjx-9qx6-jcrv x_refsource_CONFIRM
https://github.com/anthropics/claude-code/releases/tag/v2.1.251 x_refsource_MISC