CVE-2026-34956 (GCVE-0-2026-34956)
Vulnerability from cvelistv5 – Published: 2026-05-05 15:45 – Updated: 2026-05-05 16:36
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)
CWE
- CWE-120 - Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
Assigner
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| Red Hat | Fast Datapath for RHEL 7 |
cpe:/o:redhat:enterprise_linux:7::fastdatapath |
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Date Public ?
2026-03-31 00:00
Credits
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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.
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- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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