CVE-2026-34956
Openvswitch: open vswitch: denial of service via malformed ftp epasv command
MEDIUM 5.9
At a glance
- Source
- NVD
- EPSS
- EPSS 0.40 % · percentile 35 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- redhat
- NVD status
- Awaiting Analysis
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.
Weaknesses (CWE)
- CWE-120 — Buffer Copy without Checking Size of Input
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | MEDIUM 5.9 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H | redhat |
| CVSS 3.1 | MEDIUM 5.9 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H | NVD · secalert@redhat.com (Secondary) |
European references
- ENISA EUVD · EUVD-2026-27345
- GCVE · GCVE-0-2026-34956
CERT-FR advisories
- CERTFR-2026-AVI-0623 — Multiples vulnérabilités dans les produits Microsoft · cert.ssi.gouv.fr
Affected products
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |