GHSA-j8x2-777p-23fc tough cyclic delegation graphs are not detected
A TUF client library fails to detect cyclic delegations, causing stack exhaustion and process abort when processing malicious repositories.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is GHSA-j8x2-777p-23fc?
GHSA-j8x2-777p-23fc is a denial of service vulnerability in tough, published on 28 Mar 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Summary
In a TUF repository, the targets role’s signature indicates which target files are trusted by clients. The role can delegate full or partial trust to other roles, meaning that that role is trusted to sign target file metadata. Delegated roles can further delegate trust to other delegated roles. When searching for metadata about a given target, tough failed to detect cyclical role delegations.
Impact
When interacting with TUF repositories which contain cyclical role delegations, tough will fail to detect the cycles and will exhaust its stack while recursively searching the delegation graph. The exhausted call stack will cause the process to abort.
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.
Which versions are affected by GHSA-j8x2-777p-23fc?
2 open source packages ship an affected version, including tough.
| Package | Affected | Fixed in |
|---|---|---|
tough crates.io | All versions | 0.20.0 |
tough crates.io | All versions | 0.20.0 |
How do I fix GHSA-j8x2-777p-23fc?
Upgrade tough to 0.20.0 or later.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is GHSA-j8x2-777p-23fc being exploited?
There is no known exploitation of GHSA-j8x2-777p-23fc in the wild and no public exploit code.