{"cve":"CVE-2026-33586","nvd":{"published":"2026-10-07T16:17:47.643","modified":"2026-10-08T21:33:42.423","status":"Awaiting Analysis","description":"Authenticated users are able to manipulate both the SMTP\nenvelope “Envelope-from” and “From” fields when sending\nemails through OVH mail servers.\n\n\n\nDue to OVH's default SPF configuration, which\ncommonly includes include:mx.ovh.com, any authenticated user with a\nvalid OVH email account can send messages that appear to originate from any\nOVH-hosted domains using the default SPF record. Since the SPF policy\nexplicitly authorizes OVH mail servers (mx.ovh.com) to send mail on behalf of\nthese domains, forged messages successfully pass SPF validation despite\nnot being authorized by the impersonated domain owner.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:N/SI:H/SA:N/E:A","score":6.3},"cvss_v3":null,"cwes":["CWE-290","CWE-346","CWE-1188"],"references":["https://docs.ovhcloud.com/en/guides/web-cloud/email-and-collaborative-solutions/troubleshooting/email-rejected-cross-domain-spoofing"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:58:01.639778232+00:00"},"epss":{"cve":"CVE-2026-33586","score":0.00139,"percentile":0.03247,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}