CVE-2025-2888

During a snapshot rollback, the client incorrectly caches the timestamp metadata. If the client checks the cache when attempting to perform the next update, the update timestamp validation will fail, preventing the next update until the cache is cleared. Users should upgrade to tough version 0.20.0 or later and ensure any forked or derivative code is patched to incorporate the new fixes.

During a snapshot rollback, the client incorrectly caches the timestamp metadata. If the client checks the cache when attempting to perform the next update, the update timestamp validation will fail, preventing the next update until the cache is cleared. Users should upgrade to tough version 0.20.0 or later and ensure any forked or derivative code is patched to incorporate the new fixes.

## Summary TUF repositories use the timestamp role to protect against rollback events by enabling an automated process to periodically sign the role's metadata. While tough will ensure that the version of snapshot metadata in new timestamp metadata files was always greater than or equal to the previously trusted version, it will only do so after persisting the timestamp metadata to its cache. ## Impact If the tough client successfully detects a rollback event in which timestamp metadata contains outdated snapshot metadata, the invalid timestamp metadata will still be persisted to cache as trusted. tough may then subsequently incorrectly identify valid timestamp metadata as being rolled back, preventing the client from consuming valid updates. 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 [aws-security@amazon.com](mailto:aws-security@amazon.com). 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](https://github.com/theupdateframework/tuf-conformance). We would like to thank Google for collaborating on this issue through the coordinated vulnerability disclosure process.

## Summary TUF repositories use the timestamp role to protect against rollback events by enabling an automated process to periodically sign the role's metadata. While tough will ensure that the version of snapshot metadata in new timestamp metadata files was always greater than or equal to the previously trusted version, it will only do so after persisting the timestamp metadata to its cache. ## Impact If the tough client successfully detects a rollback event in which timestamp metadata contains outdated snapshot metadata, the invalid timestamp metadata will still be persisted to cache as trusted. tough may then subsequently incorrectly identify valid timestamp metadata as being rolled back, preventing the client from consuming valid updates. 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 [aws-security@amazon.com](mailto:aws-security@amazon.com). 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](https://github.com/theupdateframework/tuf-conformance). We would like to thank Google for collaborating on this issue through the coordinated vulnerability disclosure process.

Durante la reversión de una instantánea, el cliente almacena incorrectamente en caché los metadatos de la marca de tiempo. Si el cliente revisa la caché al intentar realizar la siguiente actualización, la validación de la marca de tiempo fallará, impidiendo la siguiente actualización hasta que se borre la caché. Los usuarios deben actualizar a la versión 0.20.0 o posterior y asegurarse de que cualquier código derivado o bifurcado esté parcheado para incorporar las nuevas correcciones.