CVE-2024-53085 is a vulnerability identified in the Linux kernel's Trusted Platform Module (TPM) driver, specifically related to the handling of TPM chip suspension and random number generation. The issue arises from a race condition in the tpm_pm_suspend() function, where the TPM chip is not properly locked before setting the TPM_CHIP_FLAG_SUSPENDED flag. This improper locking sequence creates a timing window during which the tpm_hwrng_read() function can be called concurrently while the TPM chip is in the process of suspending. This concurrency can lead to inconsistent or unsafe access to the TPM hardware, potentially causing unexpected behavior or corruption of TPM operations. The vulnerability is addressed by introducing a locking mechanism that ensures the TPM chip is locked before any checks or modifications to the chip's flags are performed. Additionally, the check for the TPM_CHIP_FLAG_SUSPENDED flag is moved inside the tpm_get_random() function to guarantee it is always evaluated under the protection of the lock. This fix eliminates the race condition by serializing access to the TPM chip state during suspend and random number generation operations. The affected versions correspond to specific Linux kernel commits prior to the patch. No known exploits are reported in the wild as of the publication date, and no CVSS score has been assigned yet.

For European organizations, this vulnerability could have significant implications, especially for those relying on TPM hardware for security-critical functions such as secure boot, disk encryption, cryptographic key storage, and hardware-based attestation. Exploitation of this race condition might allow an attacker with local access or the ability to execute code on the system to interfere with TPM operations, potentially undermining the integrity and reliability of cryptographic processes. This could lead to unauthorized access to sensitive keys or disruption of security services that depend on TPM functionality. Although remote exploitation is unlikely without prior system access, the vulnerability poses a risk in multi-user environments, cloud infrastructures, or virtualized systems where TPM emulation or passthrough is used. The absence of known exploits suggests the threat is currently theoretical, but the critical role of TPM in securing systems means that even a low-probability exploit could have high impact in sensitive environments.

European organizations should prioritize updating their Linux kernel to the patched versions that include the fix for CVE-2024-53085 as soon as they become available. In environments where immediate patching is not feasible, organizations should implement strict access controls to limit local user privileges and prevent untrusted code execution that could trigger the race condition. Monitoring and auditing TPM-related kernel logs may help detect anomalous TPM behavior indicative of exploitation attempts. For virtualized environments, ensure that TPM passthrough or emulation is configured securely and consider isolating TPM access to trusted virtual machines only. Additionally, organizations should review their security policies around TPM usage, including key management and hardware security module (HSM) integration, to minimize the potential impact of TPM-related vulnerabilities. Finally, maintain awareness of updates from Linux kernel maintainers and security advisories to apply patches promptly.