CVE-2026-34956 (GCVE-0-2026-34956)

Vulnerability from cvelistv5 – Published: 2026-05-05 15:45 – Updated: 2026-05-06 14:17
VLAI?
Title
Openvswitch: open vswitch: denial of service via malformed ftp epasv command
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.
Severity ?
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-120 - Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
Assigner
References
Impacted products
Vendor Product Version
Red Hat Fast Datapath for RHEL 7     cpe:/o:redhat:enterprise_linux:7::fastdatapath
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    Red Hat Fast Datapath for RHEL 7     cpe:/o:redhat:enterprise_linux:7::fastdatapath
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    Red Hat Fast Datapath for RHEL 7     cpe:/o:redhat:enterprise_linux:7::fastdatapath
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    Red Hat Fast Datapath for RHEL 7     cpe:/o:redhat:enterprise_linux:7::fastdatapath
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    Red Hat Fast Datapath for RHEL 7     cpe:/o:redhat:enterprise_linux:7::fastdatapath
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    Red Hat Fast Datapath for RHEL 7     cpe:/o:redhat:enterprise_linux:7::fastdatapath
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    Red Hat Fast Datapath for RHEL 7     cpe:/o:redhat:enterprise_linux:7::fastdatapath
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    Red Hat Fast Datapath for RHEL 7     cpe:/o:redhat:enterprise_linux:7::fastdatapath
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    Red Hat Fast Datapath for RHEL 8     cpe:/o:redhat:enterprise_linux:8::fastdatapath
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    Red Hat Fast Datapath for RHEL 8     cpe:/o:redhat:enterprise_linux:8::fastdatapath
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    Red Hat Fast Datapath for RHEL 8     cpe:/o:redhat:enterprise_linux:8::fastdatapath
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    Red Hat Fast Datapath for RHEL 8     cpe:/o:redhat:enterprise_linux:8::fastdatapath
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    Red Hat Fast Datapath for RHEL 8     cpe:/o:redhat:enterprise_linux:8::fastdatapath
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    Red Hat Fast Datapath for RHEL 8     cpe:/o:redhat:enterprise_linux:8::fastdatapath
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    Red Hat Fast Datapath for RHEL 8     cpe:/o:redhat:enterprise_linux:8::fastdatapath
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    Red Hat Fast Datapath for RHEL 8     cpe:/o:redhat:enterprise_linux:8::fastdatapath
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    Red Hat Fast Datapath for RHEL 8     cpe:/o:redhat:enterprise_linux:8::fastdatapath
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    Red Hat Fast Datapath for RHEL 8     cpe:/o:redhat:enterprise_linux:8::fastdatapath
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    Red Hat Fast Datapath for RHEL 9     cpe:/o:redhat:enterprise_linux:9::fastdatapath
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    Red Hat Fast Datapath for RHEL 9     cpe:/o:redhat:enterprise_linux:9::fastdatapath
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    Red Hat Fast Datapath for RHEL 9     cpe:/o:redhat:enterprise_linux:9::fastdatapath
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    Red Hat Fast Datapath for RHEL 9     cpe:/o:redhat:enterprise_linux:9::fastdatapath
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    Red Hat Fast Datapath for RHEL 9     cpe:/o:redhat:enterprise_linux:9::fastdatapath
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    Red Hat Fast Datapath for RHEL 9     cpe:/o:redhat:enterprise_linux:9::fastdatapath
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    Red Hat Fast Datapath for RHEL 9     cpe:/o:redhat:enterprise_linux:9::fastdatapath
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    Red Hat Fast Datapath for RHEL 9     cpe:/o:redhat:enterprise_linux:9::fastdatapath
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    Red Hat Fast Datapath for RHEL 9     cpe:/o:redhat:enterprise_linux:9::fastdatapath
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    Red Hat Red Hat Enterprise Linux 7     cpe:/o:redhat:enterprise_linux:7
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    Red Hat Red Hat OpenShift Container Platform 4     cpe:/a:redhat:openshift:4
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    Red Hat Red Hat OpenShift Container Platform 4     cpe:/a:redhat:openshift:4
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    Red Hat Red Hat OpenShift Container Platform 4     cpe:/a:redhat:openshift:4
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    Red Hat Red Hat OpenShift Container Platform 4     cpe:/a:redhat:openshift:4
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    Red Hat Red Hat OpenStack Platform 13 (Queens)     cpe:/a:redhat:openstack:13
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    Red Hat Red Hat OpenStack Platform 13 (Queens)     cpe:/a:redhat:openstack:13
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    Red Hat Red Hat OpenStack Platform 13 (Queens)     cpe:/a:redhat:openstack:13
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    Red Hat Red Hat OpenStack Platform 16.2     cpe:/a:redhat:openstack:16.2
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    Red Hat Red Hat OpenStack Platform 16.2     cpe:/a:redhat:openstack:16.2
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    Red Hat Red Hat OpenStack Platform 17.1     cpe:/a:redhat:openstack:17.1
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    Red Hat Red Hat OpenStack Platform 17.1     cpe:/a:redhat:openstack:17.1
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    Red Hat Red Hat OpenStack Platform 18.0     cpe:/a:redhat:openstack:18.0
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Date Public ?
2026-03-31 00:00
Credits
Red Hat would like to thank Seiji Sakurai for reporting this issue.
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Taxonomy of the tags.




Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.