tough root metadata version is not checked for sequential versioning

Description

Summary

When updating the root role, a TUF client must establish a trusted line of continuity to the latest set of keys. While sequentially downloading new versions of the root metadata file, tough will not check that the root object version it received was the next sequential version from the previously trusted root metadata.

Impact

The tough client will trust an outdated or rotated root role in the event that an actor with control of the storage medium of a trusted TUF repository inappropriately replaced the contents of one of the root metadata files with an adequately signed previous version. As a result, tough could trust content associated with a previous root role.

Impacted versions: < v0.20.0

Patches

A fix for this issue is available in tough version 0.20.0 and later. Customers are advised to upgrade to version 0.20.0 or later and ensure any forked or derivative code is patched to incorporate the new fixes.

Workarounds

There is no recommended work around. Customers are advised to upgrade to version 0.20.0 or the latest version.

References

If you have any questions or comments about this advisory we ask that you contact AWS/Amazon Security via our vulnerability reporting page [1] or directly via email to [email protected]. Please do not create a public GitHub issue.

[1] Vulnerability reporting page: https://aws.amazon.com/security/vulnerability-reporting

Acknowledgement

These issues were identified by the TUF-Conformance project. We would like to thank Google for collaborating on this issue through the coordinated vulnerability disclosure process.

Basic information

Type
reviewed
Severity
medium
Advisory on GitHub
Open advisory ↗
Repository advisory
Open repository advisory ↗
Source code
Browse source ↗
Published (advisory)
2025-03-28 22:12:36 UTC
Updated
2025-10-14 21:58:51 UTC
GitHub reviewed
2025-03-28 22:12:36 UTC
NVD published
2025-03-27

EPSS Score

Score Percentile
0.22% 44.54%

CVSS Scores

Base score Version Severity Vector
4.2 3.1
CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:N/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:H)
They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
5.7 4.0
CVSS:4.0/AV:N/AC:H/AT:N/PR:H/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network.
Attack complexity (AC:H)
Exploitation depends on constrained or hard-to-reproduce conditions.
Attack requirements (AT:N)
No additional preconditions are required beyond normal reachability.
Privileges required (PR:H)
High privileges are required.
User interaction (UI:P)
A user has to participate (for example click/open/approve).
Vulnerable system confidentiality impact (VC:N)
No confidentiality impact on the vulnerable system.
Vulnerable system integrity impact (VI:H)
High integrity impact on the vulnerable system.
Vulnerable system availability impact (VA:N)
No availability impact on the vulnerable system.
Subsequent system confidentiality impact (SC:N)
No confidentiality impact on subsequent systems.
Subsequent system integrity impact (SI:N)
No integrity impact on subsequent systems.
Subsequent system availability impact (SA:N)
No availability impact on subsequent systems.

Identifiers

CWEs

CWE id Name
CWE-1288 Improper Validation of Consistency within Input

Credits

  • jku (finder)
  • AdamKorcz (finder)

Affected packages (1)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem Package Vulnerable range First patched Vulnerable functions
rust tough < 0.20.0 0.20.0

References

cvelogic Threat Intelligence