Cyber Resilience

CVE-2026-25724

Access Control in Anthropic Claude Code ≤ 2.1.7

Published
06 February 2026
Modified
27 March 2026
CVSS Score v4 2.3
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0038 31th percentile
Risk Priority 15 floored blend · peak EPSS

Summary

CVE-2026-25724 is a low-severity UNIX Symbolic Link (Symlink) Following (CWE-61) vulnerability in Anthropic Claude Code. Its CVSS base score is 2.3 (Low).

Operationally, exploitation aligns with the MITRE ATT&CK technique Path Interception (T1034); ranked at the 31th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

This vulnerability is AI-related — categorised as Enterprise AI Assistants; in the Privacy and Disclosure risk domain.

The strongest mitigations our analysis identified map to AC-24 (Access Control Decisions) and AC-25 (Reference Monitor) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

Claude Code, an agentic coding tool from Anthropic, is affected by CVE-2026-25724 in versions prior to 2.1.7. The vulnerability stems from a failure to strictly enforce deny rules configured in settings.json when accessing files through symbolic links. Specifically, if a user denied access to a sensitive file like /etc/passwd, Claude Code could still read it via a symbolic link to which it had access, bypassing the deny rule enforcement. This issue is rated 7.5 on the CVSS v3.1 scale (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N) and maps to CWE-61 (Symbolic Link Following) and CWE-285 (Improper Authorization).

Attackers can exploit this vulnerability remotely without privileges or user interaction over a network connection with low complexity. By controlling or influencing a symbolic link that Claude Code accesses during its operations, an attacker can trick the tool into reading restricted files, achieving high-impact unauthorized disclosure of confidential information such as system passwords or other sensitive data pointed to by the symlinks.

The GitHub security advisory (GHSA-4q92-rfm6-2cqx) and a Terra Security blog post detail the patch in Claude Code version 2.1.7, which enforces deny rules consistently even for symlink access. Security practitioners should upgrade to version 2.1.7 or later and review settings.json configurations to ensure proper deny rules are in place, particularly in environments where Claude Code handles file operations.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Claude Code is an agentic coding tool. Prior to version 2.1.7, Claude Code failed to strictly enforce deny rules configured in settings.json when accessing files through symbolic links. If a user explicitly denied Claude Code access to a file (such…

more

as /etc/passwd) and Claude Code had access to a symbolic link pointing to that file, it was possible for Claude Code to read the restricted file through the symlink without triggering deny rule enforcement. This issue has been patched in version 2.1.7.

CWE(s)

AI Security AnalysisAI

AI Category
Enterprise AI Assistants
Risk Domain
Privacy and Disclosure
OWASP Top 10 for LLMs 2025
None mapped
Classification Reason
Matched keywords: claude

Related Threats

MITRE ATT&CK Enterprise Techniques

T1034 Path Interception Persistence
**This technique has been deprecated.
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1548 Abuse Elevation Control Mechanism Privilege Escalation
Adversaries may circumvent mechanisms designed to control privilege elevation to gain higher-level permissions.
T1548.001 Setuid and Setgid Privilege Escalation
An adversary may abuse configurations where an application has the setuid or setgid bits set in order to get code running in a different (and possibly more privileged) user’s context.
T1548.002 Bypass User Account Control Privilege Escalation
Adversaries may bypass UAC mechanisms to elevate process privileges on system.
T1548.003 Sudo and Sudo Caching Privilege Escalation
Adversaries may perform sudo caching and/or use the sudoers file to elevate privileges.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-59829Same product: Anthropic Claude Code
CVE-2026-39861Same product: Anthropic Claude Code
CVE-2025-59828Same product: Anthropic Claude Code
CVE-2026-25723Same product: Anthropic Claude Code
CVE-2026-25722Same product: Anthropic Claude Code
CVE-2025-66032Same product: Anthropic Claude Code
CVE-2026-40068Same product: Anthropic Claude Code
CVE-2026-33068Same product: Anthropic Claude Code
CVE-2025-59041Same product: Anthropic Claude Code
CVE-2025-59536Same product: Anthropic Claude Code

Affected Assets

anthropic
claude code
≤ 2.1.7

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 8 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V5.2.5

Mitigating Controls (NIST 800-53 r5) AI

Mandates that access-control decisions are made and applied to each request before access occurs.

Requires a tamperproof, always-invoked reference monitor that performs authorization checks.

Directly requires enforcement of approved authorizations for every access request, stopping improper or missing checks.

Limits granted privileges so that even a bypassed check affects fewer resources.

Information-flow enforcement on file operations must follow the resolved target rather than the link name, blocking unauthorized data movement via symlinks.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.AA-05 mostly match
prevents

PR.AA-05 mostly prevents CWE-285 via enforced policy, reviews, and least-privilege authorization decisions, yet CWE-285 remains only partially prevented because code-level check omissions or errors can still occur outside that single control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly prevent introduction of symlink-following flaws in file-handling code.

ID.RA-01 partial match
prevents

Vulnerability identification can discover existing symlink issues but does not prevent or remediate them in code.

PR.AA-01 partial match
prevents

PR.AA-01 supplies managed identities and access-request workflows that can support downstream authorization decisions, yet does nothing to enforce or verify authorization checks inside a product, leaving CWE-285 fully unaddressed by this control alone.

PR.IR-01 partial match
prevents

Network segmentation/zero-trust limits external reachability (partial prevention of exploitation) but leaves application-level authorization logic untouched, so the CWE remains fully introducible and only one facet of its risk is addressed.

PR.PS-05 none match
prevents

PR.PS-05 blocks unauthorized binaries/DNS while CWE-285 is an in-product authorization-check defect, so the control neither prevents the weakness nor removes any of its risk.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing can detect symlink-following vulnerabilities before deployment, covering most of the weakness.

prevents

Granular, policy-driven assignment of permissions and dynamic enforcement of those permissions prevent the incorrect or missing authorization decisions that lead to improper authorization flaws.

prevents

By requiring documented authorization rules and periodic policy reviews, the control makes it less likely that authorization decisions will be omitted or implemented inconsistently across applications.

prevents

Mapping access rights to information classification and business requirements forces correct enforcement of authorization decisions, blocking the incorrect authorization weakness at the policy and implementation stage.

finds

Independent reviewers evaluate whether authorization logic matches policy, thereby reducing the window in which incorrect or missing authorization checks remain in production.

finds

By requiring managers to verify that authorization decisions match policy and to remediate deviations, the control limits the persistence of incorrect or missing authorization checks.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Oracle Linux 8 (3 rules)
  • V-248577 OL 8 must enable kernel parameters to enforce Discretionary Access Control (DAC) on symlinks. prevents CWE-61
  • V-252656 The OL 8 operating system must not be configured to bypass password requirements for privilege escalation. prevents CWE-285
  • V-248581 OL 8 must require users to provide a password for privilege escalation. prevents CWE-285
RHEL 7 (3 rules)
  • V-204429 The Red Hat Enterprise Linux operating system must be configured so that users must provide a password for privilege escalation. prevents CWE-285
  • V-204430 The Red Hat Enterprise Linux operating system must be configured so that users must re-authenticate for privilege escalation. prevents CWE-285
  • V-251704 The Red Hat Enterprise Linux operating system must not be configured to bypass password requirements for privilege escalation. prevents CWE-285
RHEL 8 (1 rule)
  • V-251712 The RHEL 8 operating system must not be configured to bypass password requirements for privilege escalation. prevents CWE-285

References