CVE-2026-45860
Description
A flaw was found in the Linux kernel's netfilter connection counting (nf_conncount) feature. This vulnerability occurs when the system tracks more than eight new connections per jiffy, causing the connection list to not be cleaned up efficiently. A remote attacker could exploit this by rapidly establishing connections, leading the system to incorrectly believe it has reached its connection limit. This can result in a denial of service, preventing legitimate users from establishing new connections.
Statement
This vulnerability is rated as Moderate because exploitation requires specific packet-filtering rules to be actively configured and primarily causes transient denial of service under high connection rates without compromising system memory integrity or granting unauthorized privileges. The underlying issue only manifests on hosts configured with connection limiting modules in nftables, iptables, or Open vSwitch when handling rapid bursts of new sessions. Default enterprise kernel deployments without active connection limit filtering rules are not exposed to this behavior, and older releases such as Red Hat Enterprise Linux 8 and 9 do not contain the affected code.
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 | 7.5 |
| Attack Vector | Local | N/A | Network |
| Attack Complexity | High | N/A | Low |
| Privileges Required | Low | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | High | N/A | None |
| Integrity Impact | High | N/A | None |
| 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:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
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