Which versions of Claude Code are affected by CVE-2025-65099?

Organizations using a project via yarn plugins face notable risk from CVE-2025-65099, a code injection vulnerability rated CVSS 7.7.. A patch is available.

How to fix or mitigate CVE-2025-65099?

Within 30 days: Identify all affected systems running a project via yarn plugins and apply vendor patches as part of regular patch cycle. Validate that input sanitization is in place for all user-controlled parameters.

Claude Code CVE-2025-65099

Q: What is the CVSS score of CVE-2025-65099?

CVE-2025-65099 has a CVSS 4.0 base score of 7.7 (High). CVSS 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/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 exploitation probability: 0.2%.

HIGH

Code Injection (CWE-94)

2025-11-19 security-advisories@github.com

RCE Code Injection Claude Code

7.7

CVSS 4.0 · GitHub Advisory

Severity by source

GitHub Advisory PRIMARY

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/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

Primary rating from GitHub Advisory · only source for this CVE.

CVSS VectorGitHub Advisory

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/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

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Scope

Lifecycle Timeline

Patch released

Mar 31, 2026 - 21:13 nvd

Patch available

Analysis Generated

Mar 28, 2026 - 19:23 vuln.today

CVE Published

Nov 19, 2025 - 18:15 nvd

HIGH 7.7

DescriptionGitHub Advisory

Claude Code is an agentic coding tool. Prior to version 1.0.39, when running on a machine with Yarn 3.0 or above, Claude Code could have been tricked to execute code contained in a project via yarn plugins before the user accepted the startup trust dialog. Exploiting this would have required a user to start Claude Code in an untrusted directory and to be using Yarn 3.0 or above. This issue has been patched in version 1.0.39.

AnalysisAI

Claude Code is an agentic coding tool. Rated high severity (CVSS 7.7), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.

Technical ContextAI

This vulnerability is classified as Code Injection (CWE-94), which allows attackers to inject and execute arbitrary code within the application. Claude Code is an agentic coding tool. Prior to version 1.0.39, when running on a machine with Yarn 3.0 or above, Claude Code could have been tricked to execute code contained in a project via yarn plugins before the user accepted the startup trust dialog. Exploiting this would have required a user to start Claude Code in an untrusted directory and to be using Yarn 3.0 or above. This issue has been patched in version 1.0.39. Affected products include: Anthropic Claude Code. Version information: version 1.0.39.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Never evaluate user-controlled input as code. Use sandboxing, disable dangerous functions, apply strict input validation.