{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-34956","assignerOrgId":"53f830b8-0a3f-465b-8143-3b8a9948e749","state":"PUBLISHED","assignerShortName":"redhat","dateReserved":"2026-03-31T17:43:41.756Z","datePublished":"2026-05-05T15:45:04.638Z","dateUpdated":"2026-05-06T14:17:37.582Z"},"containers":{"cna":{"title":"Openvswitch: open vswitch: denial of service via malformed ftp epasv command","metrics":[{"other":{"content":{"value":"Moderate","namespace":"https://access.redhat.com/security/updates/classification/"},"type":"Red Hat severity rating"}},{"cvssV3_1":{"attackComplexity":"HIGH","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":5.9,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"format":"CVSS"}],"descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"Red Hat","product":"Fast Datapath for RHEL 7","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","packageName":"openvswitch","defaultStatus":"affected","cpes":["cpe:/o:redhat:enterprise_linux:7::fastdatapath"]},{"vendor":"Red Hat","product":"Fast Datapath for RHEL 7","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","packageName":"openvswitch2.10","defaultStatus":"affected","cpes":["cpe:/o:redhat:enterprise_linux:7::fastdatapath"]},{"vendor":"Red Hat","product":"Fast Datapath for RHEL 7","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","packageName":"openvswitch2.11","defaultStatus":"affected","cpes":["cpe:/o:redhat:enterprise_linux:7::fastdatapath"]},{"vendor":"Red Hat","product":"Fast Datapath for RHEL 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These are not usually configured."}],"timeline":[{"lang":"en","time":"2026-03-31T00:00:00.000Z","value":"Reported to Red Hat."},{"lang":"en","time":"2026-03-31T00:00:00.000Z","value":"Made public."}],"credits":[{"lang":"en","value":"Red Hat would like to thank Seiji Sakurai for reporting this issue."}],"providerMetadata":{"orgId":"53f830b8-0a3f-465b-8143-3b8a9948e749","shortName":"redhat","dateUpdated":"2026-05-05T15:45:04.638Z"},"x_generator":{"engine":"cvelib 1.8.0"}},"adp":[{"title":"CVE Program Container","references":[{"url":"http://www.openwall.com/lists/oss-security/2026/03/31/15"}],"providerMetadata":{"orgId":"af854a3a-2127-422b-91ae-364da2661108","shortName":"CVE","dateUpdated":"2026-05-05T16:36:17.493Z"}},{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-05-06T14:17:23.457705Z","id":"CVE-2026-34956","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-05-06T14:17:37.582Z"}}]}}