CVE-2026-34956
Publication date 5 May 2026
Last updated 13 May 2026
Ubuntu priority
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.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| openvswitch | 26.04 LTS resolute |
Needs evaluation
|
| 25.10 questing |
Needs evaluation
|
|
| 24.04 LTS noble |
Needs evaluation
|
|
| 22.04 LTS jammy |
Needs evaluation
|
|
| 20.04 LTS focal |
Needs evaluation
|
|
| 18.04 LTS bionic |
Needs evaluation
|
|
| 16.04 LTS xenial |
Not affected
|
Notes
mdeslaur
Per Debian, introduced in 2.9.0 by: https://github.com/openvswitch/ovs/commit/bd5e81a0e596dd012d11824cce69b7c80ae107c5
Patch details
| Package | Patch details |
|---|---|
| openvswitch |
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score |
5.9 · Medium
|
| Attack vector | Network |
| Attack complexity | High |
| Privileges required | None |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality | None |
| Integrity impact | None |
| Availability impact | High |
| Vector | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H |