CVE-2026-43044

Vulnerability

Description

The Linux kernel's crypto caam driver, when supplied with an HMAC key longer than the block size, copies the key and then hashed into the real key, the memory allocated for the copy was not properly rounded to DMA cache alignment. Although the rounding was calculated, it was never used for the allocation, leading to potential corruption of adjacent memory. The fix replaces kmemdup with kmalloc to allocate a larger buffer and then performs a memcpy [1].

Exploitation

Prerequisites To exploitation, an attacker would need to supply a long HMAC key that triggers copying and hashing process. This requires the ability to interact with the caam hardware crypto accelerator, typically accessible through the kernel crypto API. No authentication is no authentication requirement beyond normal system access, the attacker may be user- or program on the local system [1].

Impact of

Vulnerability If successfully exploited, the DMA corruption could lead to memory corruption in the kernel, causing denial of service (system crash or instability) or potentially enabling privilege escalation. The CVSS v3 score of 7.8 (High) reflects the high impact on confidentiality, integrity, and availability, likely due to the ability an attacker to leverage corruption for arbitrary code execution in the kernel context [1].

Mitigation

Status The Linux kernel stable commits have been merged, addressing this vulnerability. Users are advised to apply the latest stable kernel updates that include the fix. The vulnerability is not listed in CISA's Known Exploited Vulnerabilities (KEV) catalog. No specific workaround is available, other than ensuring the kernel is up to date [1].