Out-of-bounds read in Linux kernel - CVE-2026-64018
Published: July 20, 2026
Vulnerability identifier: #VU138632
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-64018
CWE-ID: CWE-125
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel
Linux kernel
Detailed vulnerability description
The vulnerability allows a local attacker to cause a denial of service.
The vulnerability exists due to an out-of-bounds read in mana_hwc_rx_event_handler() when processing hardware-modifiable WQE contents from DMA-coherent memory. A local attacker can modify the derived rx_req_idx value to cause a denial of service.
In confidential VMs such as SEV-SNP and TDX, the affected DMA-coherent memory is shared unencrypted and hardware can modify WQE contents at any time.
How to mitigate CVE-2026-64018
Install security update from vendor's repository.
Sources
- https://git.kernel.org/stable/c/01f7f893d5e1baae995beeb86cd0f3e6bb2a3b01
- https://git.kernel.org/stable/c/355e9f2b2a7887ca38100127989af3e422ba71d0
- https://git.kernel.org/stable/c/5ddc715324badd7f2641bc177db1d027b402adae
- https://git.kernel.org/stable/c/763a372d344fb12fae566d36ddb46e92454ad58c
- https://git.kernel.org/stable/c/b809d0409991b75a6cff846a5ac27c3062953f84
- https://git.kernel.org/stable/c/fa627a5eaa83fc0261f44ef3769693b886ca6e27
- https://git.kernel.org/stable/c/ff1d5af207bcea857d45fe81505f1bc4b29eaef0