CVE-2026-66689Network attack vectorHinoki check available

Unauthorized result handling via missing token validation

Published Aug 13, 2026 · Updated Aug 13, 2026

Broken access control in AcyChecker 2.0.0 and earlier allows remote attackers to invoke protected result-handling functionality. The results receiver accepts requests without validating its temporary authentication token, while related access checks do not limit the action to the main administrator. The CNA description labels access unauthenticated, but its CVSS assessment assigns low privileges; the exact operation and resulting impact remain undisclosed.

CVSS severity6.3
Medium
EPSS probability0.18%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Broken access control in AcyChecker 2.0.0 and earlier allows remote attackers to invoke protected result-handling functionality. The results receiver accepts requests without validating its temporary authentication token, while related access checks do not limit the action to the main administrator. The CNA description labels access unauthenticated, but its CVSS assessment assigns low privileges; the exact operation and resulting impact remain undisclosed.

The record

CVE
CVE-2026-66689
Published
Aug 13, 2026
Updated
Aug 13, 2026
Vendor
AcyMailing Newsletter Team
Product
AcyChecker
Classifications
CWE-862, CAPEC-1, T1190
Attack vector
network
Privileges
Unavailable

Timeline

How it unfolded

  1. Aug 13, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 13, 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=n/a <=2.0.0 changes=[{"at":"2.0.1","status":"unaffected"}]

What conditions does exploitation require?

Attack vectornetwork
Required privilegesUnavailable in this record.

What is affected?

AcyMailing Newsletter Team · AcyCheckerversion=n/a <=2.0.0 changes=[{"at":"2.0.1","status":"unaffected"}]

Published CVSS scores

6.3PatchstackCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L

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
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-862Missing Authorization
CAPEC-1Accessing Functionality Not Properly Constrained by ACLs
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

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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