CVE-2026-6966Network attack vector

Metadata forgery via duplicate signature counting

Published Apr 24, 2026 · Updated Apr 24, 2026

Signature verification in AWS tough before 0.22.0 and tuftool before 0.15.0 allows remote authenticated users to accept forged metadata. Delegated-target validation counts repeated valid signatures from the same key toward the threshold instead of requiring distinct keys. Access to one valid delegated-role signing key is required, and exploitation compromises repository metadata integrity without direct confidentiality or availability impact.

CVSS severity7.0
High
EPSS probability0.26%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Signature verification in AWS tough before 0.22.0 and tuftool before 0.15.0 allows remote authenticated users to accept forged metadata. Delegated-target validation counts repeated valid signatures from the same key toward the threshold instead of requiring distinct keys. Access to one valid delegated-role signing key is required, and exploitation compromises repository metadata integrity without direct confidentiality or availability impact.

The record

CVE
CVE-2026-6966
Published
Apr 24, 2026
Updated
Apr 24, 2026
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-347, CAPEC-475, T1553
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 24, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 24, 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?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.0AMZNCVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:H/SA:N
6.5NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
5.3AMZNCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:H/A: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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-347Improper Verification of Cryptographic Signature
CAPEC-475Signature Spoofing by Improper Validation
T1553Subvert Trust Controls

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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