CVE-2026-6662Public exploitNetwork attack vector

Token theft via unrestricted CORS policy

Published Apr 20, 2026 · Updated Apr 20, 2026

Permissive CORS in Erick Christian Copilot API 0.1 through 0.7.0 allows remote attackers to read access tokens from the Token endpoint. In src/server.ts, server.use(cors()) applies Hono's unrestricted default CORS policy globally, including to the unauthenticated /token route. Exposure requires that route to be network-reachable; a hostile origin can read its response and use the disclosed token for unauthorized Copilot API access.

CVSS severity7.3
High
EPSS probability0.18%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Permissive CORS in Erick Christian Copilot API 0.1 through 0.7.0 allows remote attackers to read access tokens from the Token endpoint. In src/server.ts, server.use(cors()) applies Hono's unrestricted default CORS policy globally, including to the unauthenticated /token route. Exposure requires that route to be network-reachable; a hostile origin can read its response and use the disclosed token for unauthorized Copilot API access.

The record

CVE
CVE-2026-6662
Published
Apr 20, 2026
Updated
Apr 20, 2026
Vendor
Erick Christian
Product
Copilot API
Classifications
CWE-346, CWE-942, T1528
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 20, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 20, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=0.1
  2. Affected versionversion=0.2
  3. Affected versionversion=0.3
  4. Affected versionversion=0.4
  5. Affected versionversion=0.5
  6. Affected versionversion=0.6
  7. Affected versionversion=0.7.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Erick Christian · Copilot APIversion=0.1; version=0.2; version=0.3; version=0.4; version=0.5; version=0.6; version=0.7.0

Published CVSS scores

7.3VulDBCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
5.5VulDBCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
7.5VulDBAV:N/AC:L/Au:N/C:P/I:P/A:P

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-346Origin Validation Error
CWE-942Permissive Cross-domain Policy with Untrusted Domains
T1528Steal Application Access Token

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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