Executive brief
A vulnerability in the Linux kernel's cryptographic driver for CAAM hardware could allow sensitive encryption keys to be leaked into system logs. This occurs when specific debug logging features are enabled, potentially exposing secret keys to local users or monitoring tools. This could compromise the confidentiality of encrypted data on the affected system.
Technical details
A vulnerability in the Linux kernel's Cryptographic Acceleration and Assurance Module (CAAM) driver (specifically in caamalg_qi2.c) allowed sensitive key material to be dumped to the kernel log. The issue stemmed from the use of print_hex_dump_debug() in the *_setkey() functions, which, when CONFIG_DYNAMIC_DEBUG is enabled, could expose raw keys during runtime. An attacker with access to kernel logs (dmesg) could potentially retrieve these secrets. The fix involves replacing the logging calls with print_hex_dump_devel(), which ensures that sensitive material is only dumped in development environments and not in production builds with dynamic debugging enabled.
Affected products
- Linux Linux Kernel 4.20 to 6.6.145, 5.10.261, 5.15.212, 6.1.178
Timeline
- 2026-07-25: disclosed
- 2026-07-25: advisory
References
- https://git.kernel.org/stable/c/1ec775f6a124cce6278ae58b7d1c78a3bc6eef23
- https://git.kernel.org/stable/c/59057f5d4e9a195c6dd61695ad3bc4481ddf4f14
- https://git.kernel.org/stable/c/6407dc85d0a4306681cf6c9be7f05e05dcb67a37
- https://git.kernel.org/stable/c/8005dc808bcce7d6cc2ae015a3cde1683bee602d
- https://git.kernel.org/stable/c/8904b425cfcafe6a820c94b9bdf4b10f7d70f9d7
- https://git.kernel.org/stable/c/bcf3cf74dfb6981e18b22cbf561f859a0f7faa26
- https://git.kernel.org/stable/c/c8cfe11e48b2a4646fa662fcaa92e14810a28d46