CVE-2026-88968
Description
A flaw was found in Claude Code. An attacker capable of executing code within the tool's sandbox can overwrite arbitrary files outside the designated workspace, leading to a sandbox escape. This issue occurs because the Edit tool verifies file paths without securing them against changes to the underlying directory structure. By replacing a verified directory with a symbolic link (a reference pointing to another file path), the attacker can redirect file modification operations to sensitive locations on the host system.
Statement
This vulnerability is rated as Important because successful exploitation permits escaping the execution sandbox and writing arbitrary host files, which compromises system integrity. Within containerized developer platforms such as Red Hat OpenShift Dev Spaces, triggering the flaw requires an attacker to convince a user to load an untrusted repository or execute hostile dependency scripts. Because the file editing mechanism checks directory paths without locking the underlying descriptors, concurrent manipulation of workspace structures allows file writes to escape intended isolation boundaries.
Mitigation
--- CME Mitigation Guidance (2026-11-04) ---
Disclaimer: The following mitigation solutions are provided as a courtesy, pending the application of an official patch. This content was generated utilizing AI tools in conjunction with data from https://cmetaxonomy.org. Customers are advised to independently evaluate and test these temporary mitigations within their own infrastructure.
The highest-value action is to bind file tool path validation to directory inodes or open file descriptors to prevent file operations from resolving symlinks outside the workspace: upgrade to Claude Code 2.1.251 (or the fixed Devspaces/Pluginregistry Rhel builds), which prevent file tools (Read, Write, Edit) from following symlinks swapped in the working directory after permission checks have executed, closing atomic symlink substitution of in-workspace parent directories after path check. Until patched, this is only a concern on macOS hosts executing Claude Code with untrusted repositories or scripts in the sandbox — Non-macOS environments are unaffected — so Do not open untrusted repositories or run untrusted dependency scripts within the Bash sandbox, and restrict write permissions on sensitive files outside the designated workspace. As a compensating measure, Ensure macOS System Integrity Protection remains enabled to block unauthorized overwrites of protected operating system binaries and configuration paths. These controls limit blast radius and contain exploitation, but they do not fix the underlying time-of-check to time-of-use symlink defect — apply the upstream patch to fully remediate.
Highest-impact CME: CME-1303 Application-Level Filesystem Access Confinement (high)
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7.7 | N/A | N/A |
| Attack Vector | Local | N/A | N/A |
| Attack Complexity | High | N/A | N/A |
| Privileges Required | None | N/A | N/A |
| User Interaction | Required | N/A | N/A |
| Scope | Changed | N/A | N/A |
| Confidentiality | High | N/A | N/A |
| Integrity Impact | High | N/A | N/A |
| Availability Impact | High | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:H
Understanding the Weakness (CWE)
Integrity,Other
Technical Impact: Alter Execution Logic; Unexpected State
The attacker can gain access to otherwise unauthorized resources.
Integrity,Other
Technical Impact: Modify Application Data; Modify Files or Directories; Modify Memory; Other
Race conditions such as this kind may be employed to gain read or write access to resources which are not normally readable or writable by the user in question.
Integrity,Other
Technical Impact: Other
The resource in question, or other resources (through the corrupted one), may be changed in undesirable ways by a malicious user.
Non-Repudiation
Technical Impact: Hide Activities
If a file or other resource is written in this method, as opposed to in a valid way, logging of the activity may not occur.
Non-Repudiation,Other
Technical Impact: Other
In some cases it may be possible to delete files a malicious user might not otherwise have access to, such as log files.
Other
Technical Impact: Unexpected State
The product may perform invalid actions when the resource is in an unexpected state.
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