CVE-2022-23948 is a high-severity vulnerability affecting Keylime versions prior to 6.3.0. Keylime is an open-source remote attestation framework designed to verify the integrity of hosts in cloud and edge computing environments. The vulnerability is classified under CWE-200, which pertains to information exposure. Specifically, the flaw resides in the Keylime agent's logic for verifying secure mounts. The agent attempts to ensure that sensitive data, such as cryptographic secrets, are stored only on secure mounts. However, this logic can be bypassed if an attacker creates unprivileged mounts prior to the agent's check. These pre-existing mounts can trick the agent into believing the environment is secure, thereby allowing secrets to be leaked to other processes running on the same host. The vulnerability does not require any privileges or user interaction to exploit (CVSS vector: AV:N/AC:L/PR:N/UI:N), making it remotely exploitable over the network without authentication. The impact is a high confidentiality breach, as secrets intended to be protected by secure mounts can be accessed by unauthorized processes. There is no indication of integrity or availability impact. No known exploits are currently reported in the wild, but the vulnerability's nature and ease of exploitation make it a significant risk, especially in multi-tenant or shared environments where isolation is critical. The issue was addressed in Keylime version 6.3.0, which presumably includes improved mount verification logic to prevent this bypass.

For European organizations, especially those operating cloud infrastructure, edge computing, or environments relying on Keylime for host attestation and security, this vulnerability poses a serious risk of unauthorized disclosure of sensitive cryptographic material. Such exposure could lead to further compromise of secure communications, authentication tokens, or encryption keys, undermining the trustworthiness of the entire security framework. Organizations in sectors like finance, healthcare, critical infrastructure, and government, which often deploy Keylime or similar attestation tools to enforce security policies, could face regulatory and compliance repercussions under GDPR and other data protection laws if sensitive data is leaked. The breach of confidentiality could also facilitate lateral movement by attackers within networks, increasing the risk of broader compromise. Given the vulnerability does not require privileges or user interaction, attackers could exploit it remotely, increasing the threat surface. The absence of known exploits in the wild suggests that timely patching can effectively mitigate risk, but delayed remediation could expose organizations to targeted attacks.

European organizations should immediately assess their use of Keylime and identify any deployments running versions prior to 6.3.0. The primary mitigation is to upgrade Keylime agents and servers to version 6.3.0 or later, where the mount verification logic has been corrected. Additionally, organizations should implement strict mount namespace isolation and restrict the ability for unprivileged users or processes to create mounts that could interfere with security checks. Employing mandatory access controls (e.g., SELinux, AppArmor) to limit mount operations and monitoring mount points for unauthorized changes can provide additional defense layers. Regular audits of the host environment to detect suspicious mounts or processes accessing sensitive files should be conducted. Network segmentation and limiting access to hosts running Keylime agents can reduce exposure. Finally, organizations should review and enhance their key management and secret storage practices to minimize the impact of potential leaks, including using hardware security modules (HSMs) or secure enclaves where feasible.