CVE-2024-23332 is a medium-severity vulnerability affecting the Notary Project specifications up to version 1.0.1. The Notary Project provides a standardized framework for securing software supply chains by authenticating container images and other OCI (Open Container Initiative) artifacts through digital signatures. This vulnerability arises from improper handling of artifact signature validity periods, specifically an operation on a resource after its expiration or release (CWE-672). In scenarios where an attacker has compromised a container registry, they can serve outdated OCI artifacts with expired or revoked signatures. If artifact consumers use relaxed trust policies such as 'permissive' instead of 'strict', they may accept these outdated artifacts, potentially exposing themselves to known vulnerabilities or malicious code embedded in those older versions. The Notary Project allows artifact publishers to specify signature expiry during signing, enabling short-lived signatures and periodic resigning to ensure consumers only receive current, valid artifacts. Additionally, revocation mechanisms allow publishers to invalidate older certificates independently of artifact management capabilities. However, the vulnerability exists because some consumers may bypass strict signature validation, allowing rollback attacks where attackers substitute newer artifacts with older, vulnerable ones. The CVSS 3.1 score of 4.0 reflects a network attack vector requiring high complexity, high privileges, and user interaction, with no confidentiality impact but low integrity and availability impacts. No known exploits are reported in the wild yet. This vulnerability highlights the critical importance of enforcing strict signature validation policies and leveraging short-lived certificates with revocation to maintain artifact integrity in compromised environments.

For European organizations, especially those relying on containerized workloads and OCI artifacts in their software supply chains, this vulnerability poses a risk of deploying outdated or compromised software components. Attackers controlling a container registry could perform rollback attacks, causing systems to run vulnerable or malicious code, potentially leading to service disruptions or integrity breaches. This risk is heightened in sectors with stringent supply chain security requirements such as finance, healthcare, and critical infrastructure. The impact on confidentiality is minimal, but integrity and availability could be affected if attackers exploit known vulnerabilities in outdated artifacts. Organizations with relaxed trust policies or lacking automated artifact resigning and revocation processes are particularly vulnerable. Given the increasing adoption of container technologies across Europe, the threat could affect a broad range of enterprises, from startups to large-scale cloud providers. However, the requirement for high privileges and user interaction to exploit reduces the likelihood of widespread automated attacks, making targeted attacks more probable. The vulnerability also underscores the importance of supply chain security governance and compliance with European cybersecurity frameworks.

European organizations should enforce strict signature validation policies ('strict' or equivalent) in their artifact consumption workflows to reject expired or revoked signatures. Implement automated processes for short-lived signature issuance and periodic artifact resigning to minimize the window of exposure. Utilize the Notary Project's revocation features to promptly invalidate compromised or outdated certificates. Container registries should be secured with robust access controls and monitoring to prevent unauthorized modifications. Integrate continuous supply chain security scanning to detect usage of outdated or vulnerable artifacts. Educate DevOps and security teams on the risks of permissive trust policies and rollback attacks. Where urgent deployment scenarios require relaxed policies, implement compensating controls such as additional runtime security monitoring and anomaly detection. Regularly update Notary Project components to versions beyond 1.0.1 once patches are available. Finally, conduct incident response drills simulating registry compromise to validate detection and mitigation capabilities.