CVE-2026-99220
Description
A flaw was found in the Linux kernel. A local, unprivileged attacker could exploit this vulnerability to cause a Denial of Service (DoS) by crashing the system. The issue occurs within the asymmetric key management subsystem when applying restrictions using a key that lacks identifiers, such as a PKCS#8 private key. When an operation subsequently attempts to add a key against this restriction, the kernel unconditionally dereferences an empty identifier field, triggering a null-pointer dereference and kernel panic.
Statement
This vulnerability is rated as having Moderate severity because an unprivileged local user can trigger an immediate denial of service by causing a system crash, but cannot achieve arbitrary code execution, privilege escalation, or data exfiltration. Default enterprise Linux environments permit unprivileged user access to keyring operations, allowing any authenticated local account to invoke keyring restrictions. However, exploitation requires local system access and is strictly confined to crashing the host without compromising data confidentiality or integrity.
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).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 5.5 | N/A | N/A |
| Attack Vector | Local | N/A | N/A |
| Attack Complexity | Low | N/A | N/A |
| Privileges Required | Low | N/A | N/A |
| User Interaction | None | N/A | N/A |
| Scope | Unchanged | N/A | N/A |
| Confidentiality | None | N/A | N/A |
| Integrity Impact | None | N/A | N/A |
| Availability Impact | High | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Crash, Exit, or Restart
NULL pointer dereferences usually result in the failure of the process unless exception handling (on some platforms) is available and implemented. Even when exception handling is being used, it can still be very difficult to return the software to a safe state of operation.
Integrity,Confidentiality
Technical Impact: Execute Unauthorized Code or Commands; Read Memory; Modify Memory
In rare circumstances, when NULL is equivalent to the 0x0 memory address and privileged code can access it, then writing or reading memory is possible, which may lead to code execution.
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