CVE-2026-53016
Description
A flaw was found in the Linux kernel's cryptographic coprocessor (CCP) driver. When processing AF_ALG rfc3686-ctr-aes-ccp requests, the ccp_aes_complete() function attempts to restore more data than the allocated buffer for the Initialization Vector (IV) can hold. This leads to a buffer overrun, which can result in memory corruption within the kernel.
Statement
An out-of-bounds write exists in the AMD CCP AES completion path because ccp_aes_complete() restores AES_BLOCK_SIZE bytes into req iv even when the selected skcipher exposes a shorter IV. For RFC3686 CTR AES through AF_ALG, the caller IV can be 8 bytes while the driver copies 16 bytes, overwriting memory past the provided IV buffer. For the CVSS the PR:L is used because a local user or local process can reach AF_ALG crypto interfaces without needing full administrator privileges when the vulnerable CCP backed algorithm is available. The issue is not network reachable and requires local code execution on a system with the affected CCP crypto driver and algorithm available.
Mitigation
To mitigate this issue, prevent module ccp-crypto from being loaded. Please see https://access.redhat.com/solutions/41278 for how to blacklist a kernel module to prevent it from loading automatically.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7 | N/A | 7 |
| Attack Vector | Local | N/A | Local |
| Attack Complexity | High | N/A | High |
| Privileges Required | Low | N/A | Low |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | High | N/A | High |
| Integrity Impact | High | N/A | High |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
cve.org: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Understanding the Weakness (CWE)
Integrity,Confidentiality,Availability
Technical Impact: Read Memory; Modify Memory; Execute Unauthorized Code or Commands
Buffer overflows often can be used to execute arbitrary code, which is usually outside the scope of a program's implicit security policy. This can often be used to subvert any other security service.
Availability
Technical Impact: Modify Memory; DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU)
Buffer overflows generally lead to crashes. Other attacks leading to lack of availability are possible, including putting the program into an infinite loop.
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