CVE-2026-46319
Description
A flaw was found in the Linux kernel. A race condition in the act_ct module, specifically during the flow table lookup, can lead to a Use-After-Free (UAF) vulnerability. This occurs because a critical lock is released prematurely, allowing a memory object to be freed while still in use. An attacker could potentially exploit this to achieve privilege escalation.
Statement
This vulnerability is rated as Moderate impact because successful exploitation requires local execution privileges and winning a narrow race condition during network traffic control flow table initialization. Under standard configurations, defining traffic control actions requires elevated network administration privileges, which significantly confines the attack surface unless unprivileged user namespaces are available. While a use-after-free condition could potentially allow a local user to escalate privileges or destabilize the system, the tight timing window makes practical exploitation complex.
Mitigation
To mitigate this issue, prevent module act_ct 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 | 7.8 |
| Attack Vector | Local | N/A | Local |
| Attack Complexity | High | N/A | Low |
| 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:L/PR:L/UI:N/S:U/C:H/I:H/A:H
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