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TI-2026-06098 Aliases CVE-2026-6966GHSA-8m7c-8m39-rv4x

Signature Threshold Bypass in awslabs/tough Delegated Roles

Priority LOW 31CWE-347Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
High
Attack requirements
Present
Impact type
Security bypass
Confidentiality · integrity · availability
None · High · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-347.

Summary

Improper verification of cryptographic signature uniqueness in delegated role validation in awslabs/tough before tough-v0.22.0 allows remote authenticated users to bypass the TUF signature threshold requirement by duplicating a valid signature, causing the client to accept forged delegated role metadata. We recommend you upgrade to tough-v0.22.0 / tuftool-v0.15.0.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00283 20th percentileScored 2026-11-07
Fix Fixed tough (crates.io): 0.22.0tuftool (crates.io): 0.15.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
AWStough0.9.0 – 0.21—No fix listedCNA
AWStuftoolup to 0.14—No fix listedCNA
—tough (crates.io)before 0.22.00.22.0Patch availableGHSA-8m7c-8m39-rv4x
—tuftool (crates.io)before 0.15.00.15.0Patch availableGHSA-8m7c-8m39-rv4x
  • tough VendorAWS Affected 0.9.0 – 0.21 Fixed in — No fix listed CNA
  • tuftool VendorAWS Affected up to 0.14 Fixed in — No fix listed CNA
  • tough (crates.io) Vendor— Affected before 0.22.0 Fixed in 0.22.0 Patch available GHSA-8m7c-8m39-rv4x
  • tuftool (crates.io) Vendor— Affected before 0.15.0 Fixed in 0.15.0 Patch available GHSA-8m7c-8m39-rv4x

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:amazon:tough:*:*:*:*:*:rust:*:*before 0.22.0VulnerableAWS
cpe:2.3:a:amazon:tuftool:*:*:*:*:*:rust:*:*before 0.15.0VulnerableAWS
  • cpe:2.3:a:amazon:tough:*:*:*:*:*:rust:*:* Versions before 0.22.0 Vulnerable ·AWS
  • cpe:2.3:a:amazon:tuftool:*:*:*:*:*:rust:*:* Versions before 0.15.0 Vulnerable ·AWS

Remediation

  • Fix · GHSA-8m7c-8m39-rv4x tough (crates.io) Fixed in 0.22.0 Advisory →
  • Fix · GHSA-8m7c-8m39-rv4x tuftool (crates.io) Fixed in 0.15.0 Advisory →

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Advisory ·

    AWS tough, tuftool — aws.amazon.com/security/security-bulletins/2026-019-aws

    3 records Highest priority Priority LOW 3 LOW

    Other records, highest priority first

    • TI-2026-06100 Multiple Path Traversal Variants in awslabs/toughPriority LOW 32
    • TI-2026-06099 Missing Delegated Metadata Validation in awslabs/toughPriority LOW 31
    Show all 3 records → Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-6966
  2. 2026-10-03 Alias added: GHSA-8m7c-8m39-rv4x
  3. 2026-10-20 Affected versions changed · CNA

References

Patch 4

Advisory 3

Other 2

  • TI-2020-11868 Improper verification of signature threshold in tough CVSS 3.1HIGH 8.6
  • TI-2021-17989 Improper sanitization of delegated role names in tough CVSS 3.1HIGH 8.2
  • TI-2021-17988 Improper sanitization of target names in tough CVSS 3.1HIGH 8.2
  • TI-2026-06100 Multiple Path Traversal Variants in awslabs/tough CVSS 4.0HIGH 7.1
  • TI-2026-06099 Missing Delegated Metadata Validation in awslabs/tough CVSS 4.0HIGH 7.1
  • TI-2025-02523 Improper timestamp caching during snapshot rollback in tough CVSS 4.0MEDIUM 5.7
See all 9 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences