CVE-2026-21852

medium

Description

Claude Code is an agentic coding tool. Prior to version 2.0.65, vulnerability in Claude Code's project-load flow allowed malicious repositories to exfiltrate data including Anthropic API keys before users confirmed trust. An attacker-controlled repository could include a settings file that sets ANTHROPIC_BASE_URL to an attacker-controlled endpoint and when the repository was opened, Claude Code would read the configuration and immediately issue API requests before showing the trust prompt, potentially leaking the user's API keys. Users on standard Claude Code auto-update have received this fix already. Users performing manual updates are advised to update to version 2.0.65, which contains a patch, or to the latest version.

References

References
More

https://www.darkreading.com/cloud-security/amazon-q-vs-extension-flaw-leads-cloud-credential-theft

https://www.wiz.io/blog/amazon-q-vulnerability

https://www.theregister.com/2026/02/26/clade_code_cves/

https://www.darkreading.com/application-security/flaws-claude-code-developer-machines-risk

https://thehackernews.com/2026/02/claude-code-flaws-allow-remote-code.html

https://securityaffairs.com/188508/security/untrusted-repositories-turn-claude-code-into-an-attack-vector.html

https://research.checkpoint.com/2026/rce-and-api-token-exfiltration-through-claude-code-project-files-cve-2025-59536/

https://blog.checkpoint.com/research/check-point-researchers-expose-critical-claude-code-flaws/

https://github.com/Perufitlife/dotclaude-security

https://github.com/blaxkmiradev/CVE-2026-21847-Hardcoded-AES-Encryption-Key-in-DPDC-Customer-Portal

https://github.com/ezphongdo-cmyk/guardvibe

https://github.com/endiselmanaj/macos-vuln-check

https://github.com/TreRB/ai-ide-config-guard

https://github.com/MQ-06/Claude-Code-Security_ResearchPaper

https://github.com/pathakabhi24/LLM-MCP-Security-Field-Guide

https://github.com/enchanter-ai/hydra

https://github.com/sattyamjjain/agent-audit-kit

https://github.com/psnluiz/secure-claude-code

https://github.com/goklab/guardvibe

https://github.com/jnMetaCode/shellward

https://github.com/M0broot/CVE-Archive

https://github.com/atiilla/CVE-2026-21852-PoC

https://github.com/jim2478/CVE-Archive

https://github.com/anthropics/claude-code/security/advisories/GHSA-jh7p-qr78-84p7

Details

Source: Mitre, NVD

Published: 2026-01-21

Updated: 2026-02-02

Risk Information

CVSS v2

Base Score: 7.8

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:N/A:N

Severity: High

CVSS v3

Base Score: 7.5

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Severity: High

CVSS v4

Base Score: 5.3

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N

Severity: Medium

EPSS

EPSS: 0.29116