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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-34956 Detail

Description

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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

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URL Source(s) Tag(s)
http://www.openwall.com/lists/oss-security/2026/03/31/15 CVE
https://access.redhat.com/security/cve/CVE-2026-34956 Red Hat, Inc.
https://bugzilla.redhat.com/show_bug.cgi?id=2453459 Red Hat, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-120 Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') Red Hat, Inc.  

Change History

2 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-34956
NVD Published Date:
05/05/2026
NVD Last Modified:
05/05/2026
Source:
Red Hat, Inc.