CVE-2025-2887 is a vulnerability identified in AWS tough, an open-source library used to implement The Update Framework (TUF) for secure software update systems. The issue arises during a target rollback scenario where the client fails to detect rollback attacks specifically for delegated targets. Delegated targets are subsets of the overall target metadata that can be managed by different entities. Due to this flaw, the client may accept and fetch target files from an incorrect or outdated source, leading to the possibility of altered or malicious target contents being accepted as legitimate. This undermines the core security guarantees of TUF, which aims to prevent rollback and freeze attacks in software update processes. The vulnerability affects tough version 0.1.0 and was addressed in version 0.20.0 and later. The CVSS 4.0 score is 5.7 (medium severity), reflecting network attack vector with high attack complexity, requiring high privileges and user interaction, and causing high impact on integrity and availability but no impact on confidentiality. No known exploits have been reported in the wild, but the risk remains for organizations using vulnerable versions. The vulnerability is classified under CWE-1025 (Comparison Using Wrong Factors), indicating a logic error in how rollback detection is implemented. This can lead to trust violations in software supply chains if attackers can manipulate update metadata or intercept update requests.

For European organizations, the primary impact of CVE-2025-2887 lies in the potential compromise of software update integrity. Organizations using AWS tough in their update infrastructure risk accepting outdated or malicious software versions, which can lead to system compromise, data corruption, or service disruption. This is particularly critical for sectors relying on secure and timely software updates such as finance, healthcare, critical infrastructure, and government agencies. The vulnerability could facilitate supply chain attacks, allowing adversaries to introduce backdoors or malware via manipulated update targets. Given the requirement for high privileges and user interaction, exploitation is less trivial but remains a significant risk in environments where insiders or sophisticated attackers operate. The availability of patched versions means organizations that delay updates remain exposed. The impact on confidentiality is limited, but integrity and availability impacts are high, potentially causing operational disruptions and loss of trust in update mechanisms.

To mitigate CVE-2025-2887, organizations should immediately upgrade all instances of AWS tough to version 0.20.0 or later, which contains the fix for the rollback detection flaw. Additionally, any forked or derivative codebases that implement or extend tough must be reviewed and patched to incorporate the updated rollback detection logic. Organizations should audit their software update pipelines to ensure no legacy versions remain in use. Implementing strict access controls and monitoring for unusual update-related activities can help detect attempts to exploit this vulnerability. Employing defense-in-depth strategies such as cryptographic verification of update metadata and files, network segmentation, and limiting user privileges reduces the risk of exploitation. Regular security assessments and penetration testing focused on supply chain security will help identify residual risks. Finally, educating developers and administrators about the importance of timely patching and secure update practices is critical.