Name: CVE-2026-34956: Buffer Copy without Checking Size of Input
Creator: Rapid7
Published: 2026-05-05T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2026-34956, CWE-120, CVSS 5.9, EPSS 0.00635

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.

CVSS Details

CVSS 3.1 Base Score: 5.9
CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Redhat_linux	—	No solution exists	Jul 17, 2026	Mar 31, 2026

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CVSS Details

Covered by Rapid7

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