CVE-2025-52882Public exploitNetwork attack vector

File disclosure via missing WebSocket origin validation

Published Jun 24, 2025 · Updated Jun 24, 2025

Improper authorization in Anthropic Claude Code IDE extensions allows remote attackers to read local files via cross-origin WebSockets. The extensions' local WebSocket servers accept connections from arbitrary webpage origins instead of validating the Origin header. A user must visit an attacker-controlled page; VS Code can expose arbitrary files and, with an open Jupyter notebook plus prompt acceptance, code execution.

CVSS severity8.8
High
EPSS probability0.34%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authorization in Anthropic Claude Code IDE extensions allows remote attackers to read local files via cross-origin WebSockets. The extensions' local WebSocket servers accept connections from arbitrary webpage origins instead of validating the Origin header. A user must visit an attacker-controlled page; VS Code can expose arbitrary files and, with an open Jupyter notebook plus prompt acceptance, code execution.

The record

CVE
CVE-2025-52882
Published
Jun 24, 2025
Updated
Jun 24, 2025
Vendor
Anthropic
Product
Claude Code
Classifications
CWE-285, CWE-1385, T1005, T1189
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 24, 2025CVE publishedPublication date reported by the CVE source.
  2. Jun 24, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=>= 0.2.116 < 1.0.24

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Anthropic · Claude Codeversion=>= 0.2.116 < 1.0.24

Published CVSS scores

8.8GitHubCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-285Improper Authorization
CWE-1385Missing Origin Validation in WebSockets
T1005Data from Local System
T1189Drive-by Compromise

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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