CVE-2026-88968 (GCVE-0-2026-88968)

Vulnerability from cvelistv5 – Published: 2026-11-03 20:08 – Updated: 2026-11-03 21:29
VLAI
Title
Claude Code: TOCTOU Race in Edit Tool Allows File Writes Outside the Workspace
Summary
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.
Severity
7.7 (High)
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
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-11-03 21:29 UTC
CWE
  • CWE-59 - Improper Link Resolution Before File Access ('Link Following')
  • CWE-367 - Time-of-check Time-of-use (TOCTOU) Race Condition
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7993 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
anthropics claude-code Affected: < 2.1.251
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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