Openvswitch: open vswitch: denial of service via malformed ftp epasv command
Priority LOW 27CWE-120Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Deferred Red Hat: fix deferred
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-120 and the CVSS impact.
Summary
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.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00405 35th percentileScored 2026-11-07
Fix Deferred Red Hat: fix deferred
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Red Hat | Fast Datapath for RHEL 7 | — | — | No fix listed | CNA |
| Red Hat | Fast Datapath for RHEL 7 | — | — | No fix listed | CNA |
| Red Hat | Fast Datapath for RHEL 7 | — | — | No fix listed | CNA |
| Red Hat | Fast Datapath for RHEL 7 | — | — | No fix listed | CNA |
| Red Hat | Fast Datapath for RHEL 7 | — | — | No fix listed | CNA |
| Red Hat | Fast Datapath for RHEL 7 | — | — | No fix listed | CNA |
| Red Hat | Fast Datapath for RHEL 7 | — | — | No fix listed | CNA |
| Red Hat | Fast Datapath for RHEL 7 | — | — | No fix listed | CNA |
| Red Hat | Fast Datapath for RHEL 8 | — | — | No fix listed | CNA |
| Red Hat | Fast Datapath for RHEL 8 | — | — | No fix listed | CNA |
| Red Hat | Fast Datapath for RHEL 8 | — | — | No fix listed | CNA |
| Red Hat | Fast Datapath for RHEL 8 | — | — | No fix listed | CNA |
| Red Hat | Fast Datapath for RHEL 8 | — | — | No fix listed | CNA |
| Red Hat | Fast Datapath for RHEL 8 | — | — | No fix listed | CNA |
| Red Hat | Fast Datapath for RHEL 8 | — | — | No fix listed | CNA |
| Red Hat | Fast Datapath for RHEL 8 | — | — | No fix listed | CNA |
| Red Hat | Fast Datapath for RHEL 8 | — | — | No fix listed | CNA |
| Red Hat | Fast Datapath for RHEL 8 | — | — | No fix listed | CNA |
| Red Hat | Fast Datapath for RHEL 9 | — | — | No fix listed | CNA |
| Red Hat | Fast Datapath for RHEL 9 | — | — | No fix listed | CNA |
| Red Hat | Fast Datapath for RHEL 9 | — | — | No fix listed | CNA |
| Red Hat | Fast Datapath for RHEL 9 | — | — | No fix listed | CNA |
| Red Hat | Fast Datapath for RHEL 9 | — | — | No fix listed | CNA |
| Red Hat | Fast Datapath for RHEL 9 | — | — | No fix listed | CNA |
| Red Hat | Fast Datapath for RHEL 9 | — | — | No fix listed | CNA |
| Red Hat | Fast Datapath for RHEL 9 | — | — | No fix listed | CNA |
| Red Hat | Fast Datapath for RHEL 9 | — | — | No fix listed | CNA |
| Red Hat | Red Hat Enterprise Linux 7 | — | — | No fix listed | CNA |
| Red Hat | Red Hat OpenShift Container Platform 4 | — | — | No fix listed | CNA |
| Red Hat | Red Hat OpenShift Container Platform 4 | — | — | No fix listed | CNA |
| Red Hat | Red Hat OpenShift Container Platform 4 | — | — | No fix listed | CNA |
| Red Hat | Red Hat OpenShift Container Platform 4 | — | — | No fix listed | CNA |
| Red Hat | Red Hat OpenShift Container Platform 4 | — | — | No fix listed | CNA |
| Red Hat | Red Hat OpenStack Platform 13 (Queens) | — | — | No fix listed | CNA |
| Red Hat | Red Hat OpenStack Platform 13 (Queens) | — | — | No fix listed | CNA |
| Red Hat | Red Hat OpenStack Platform 13 (Queens) | — | — | No fix listed | CNA |
| Red Hat | Red Hat OpenStack Platform 16.2 | — | — | No fix listed | CNA |
| Red Hat | Red Hat OpenStack Platform 16.2 | — | — | No fix listed | CNA |
| Red Hat | Red Hat OpenStack Platform 17.1 | — | — | No fix listed | CNA |
| Red Hat | Red Hat OpenStack Platform 17.1 | — | — | No fix listed | CNA |
| Red Hat | Red Hat OpenStack Platform 18.0 | — | — | No fix listed | CNA |
- Fast Datapath for RHEL 7 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Fast Datapath for RHEL 7 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Fast Datapath for RHEL 7 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Fast Datapath for RHEL 7 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Fast Datapath for RHEL 7 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Fast Datapath for RHEL 7 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Fast Datapath for RHEL 7 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Fast Datapath for RHEL 7 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Fast Datapath for RHEL 8 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Fast Datapath for RHEL 8 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Fast Datapath for RHEL 8 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Fast Datapath for RHEL 8 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Fast Datapath for RHEL 8 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Fast Datapath for RHEL 8 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Fast Datapath for RHEL 8 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Fast Datapath for RHEL 8 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Fast Datapath for RHEL 8 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Fast Datapath for RHEL 8 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Fast Datapath for RHEL 9 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Fast Datapath for RHEL 9 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Fast Datapath for RHEL 9 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Fast Datapath for RHEL 9 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Fast Datapath for RHEL 9 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Fast Datapath for RHEL 9 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Fast Datapath for RHEL 9 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Fast Datapath for RHEL 9 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Fast Datapath for RHEL 9 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat Enterprise Linux 7 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat OpenShift Container Platform 4 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat OpenShift Container Platform 4 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat OpenShift Container Platform 4 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat OpenShift Container Platform 4 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat OpenShift Container Platform 4 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat OpenStack Platform 13 (Queens) VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat OpenStack Platform 13 (Queens) VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat OpenStack Platform 13 (Queens) VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat OpenStack Platform 16.2 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat OpenStack Platform 16.2 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat OpenStack Platform 17.1 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat OpenStack Platform 17.1 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat OpenStack Platform 18.0 VendorRed Hat Affected — Fixed in — No fix listed CNA
CPE names CNA · 9
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:/o:redhat:enterprise_linux:7::fastdatapath | 7 | — | Red Hat |
| cpe:/o:redhat:enterprise_linux:8::fastdatapath | 8 | — | Red Hat |
| cpe:/o:redhat:enterprise_linux:9::fastdatapath | 9 | — | Red Hat |
| cpe:/o:redhat:rhel_els:7 | 7 | — | Red Hat |
| cpe:/a:redhat:openshift:4 | 4 | — | Red Hat |
| cpe:/a:redhat:openstack:13 | 13 | — | Red Hat |
| cpe:/a:redhat:openstack:16.2 | 16.2 | — | Red Hat |
| cpe:/a:redhat:openstack:17.1 | 17.1 | — | Red Hat |
| cpe:/a:redhat:openstack:18.0 | 18.0 | — | Red Hat |
- cpe:/o:redhat:enterprise_linux:7::fastdatapath Versions 7 — ·Red Hat
- cpe:/o:redhat:enterprise_linux:8::fastdatapath Versions 8 — ·Red Hat
- cpe:/o:redhat:enterprise_linux:9::fastdatapath Versions 9 — ·Red Hat
- cpe:/o:redhat:rhel_els:7 Versions 7 — ·Red Hat
- cpe:/a:redhat:openshift:4 Versions 4 — ·Red Hat
- cpe:/a:redhat:openstack:13 Versions 13 — ·Red Hat
- cpe:/a:redhat:openstack:16.2 Versions 16.2 — ·Red Hat
- cpe:/a:redhat:openstack:17.1 Versions 17.1 — ·Red Hat
- cpe:/a:redhat:openstack:18.0 Versions 18.0 — ·Red Hat
Remediation
No fixed version listed by the sources yet.
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Fast Datapath for RHEL 7 | Affected | No fix yet: Fix deferred |
| Fast Datapath for RHEL 8 | Affected | No fix yet: Fix deferred |
| Fast Datapath for RHEL 9 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 7 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Container Platform 4 | Affected | No fix yet: Fix deferred |
| Red Hat OpenStack Platform 13 (Queens) | Affected | No fix yet: Fix deferred |
| Red Hat OpenStack Platform 16.2 | Affected | No fix yet: Fix deferred |
| Red Hat OpenStack Platform 17.1 | Affected | No fix yet: Fix deferred |
| Red Hat OpenStack Platform 18.0 | Affected | No fix yet: Fix deferred |
Timeline
- 2026-10-02 Threatist record created from CVE-2026-34956
- 2026-10-03 Alias added: GHSA-q5f5-xxh8-jx9h
References
More Red Hat vulnerabilities
- TI-2019-15875 Protection mechanism failure in Jenkins Pipeline: Groovy Plugin KEVCVSS 3.1CRITICAL 9.9
- TI-2019-15874 Protection mechanism failure in Jenkins Script Security Plugin KEVCVSS 3.1CRITICAL 9.9
- TI-2019-08259 Underflow in PHP-FPM can lead to RCE KEVCVSS 3.1CRITICAL 9.8
- TI-2019-05363 Code injection in Elastic Kibana KEVCVSS 3.1CRITICAL 10.0
- TI-2019-03949 Out-of-bounds write in ESXi and Horizon DaaS KEVCVSS 3.1CRITICAL 9.8
- TI-2018-16080 A code execution vulnerability exists in the Stapler web framework used by Jenkins 2.153… KEVCVSS 3.1CRITICAL 9.8
Sources
- CVE-2026-34956 · CVE Program
- CVE-2026-34956 · NVD
- FIRST EPSS
- GHSA-q5f5-xxh8-jx9h · GitHub Advisory Database · CC BY 4.0
- CVE-2026-34956 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences