CVE-2026-34956 MEDIUM

CVE-2026-34956: Openvswitch: open vswitch: denial of service via malformed ftp epasv command

Vendor Red Hat
Product Fast Datapath for RHEL 7
Weakness CWE-120
Published May 5, 2026
Last update May 6, 2026
View on NVD All CVEs

CVSS base score

5.9/10
Attack vector Network
Attack complexity High
Privileges required None
User interaction None
Confidentiality None
Integrity None

CVSS vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

What the vulnerability does

01Description

A flaw was found in Open vSwitch. When Open vSwitch is configured with a conntrack flow using FTP helpers over the userspace datapath, a remote attacker can send a specially crafted FTP stream with an EPASV command exceeding 255 characters. This heap access error can lead to a crash, resulting in a Denial of Service (DoS) for the affected system.

Key dates

02Disclosure timeline

May 5, 2026 CVE published
May 6, 2026 Record updated