CVE-2026-33586
MEDIUM
6,3
Source: a6d3dc9e-0591-4a13-bce7-0f5b31ff6158
Attack Vector: network
Attack Complexity: low
Privileges Required: low
User Interaction: none
Confidentiality: N/A
Integrity: N/A
Availability: N/A
Description
AI Translation Available
Authenticated users are able to manipulate both the SMTP
envelope “Envelope-from” and “From” fields when sending
emails through OVH mail servers.
Due to OVH's default SPF configuration, which
commonly includes include:mx.ovh.com, any authenticated user with a
valid OVH email account can send messages that appear to originate from any
OVH-hosted domains using the default SPF record. Since the SPF policy
explicitly authorizes OVH mail servers (mx.ovh.com) to send mail on behalf of
these domains, forged messages successfully pass SPF validation despite
not being authorized by the impersonated domain owner.
290
Authentication Bypass by Spoofing
IncompleteCommon Consequences
Security Scopes Affected:
Access Control
Potential Impacts:
Bypass Protection Mechanism
Gain Privileges Or Assume Identity
Applicable Platforms
All platforms may be affected
346
Origin Validation Error
DraftCommon Consequences
Security Scopes Affected:
Access Control
Other
Potential Impacts:
Gain Privileges Or Assume Identity
Varies By Context
Applicable Platforms
Technologies:
Not Technology-Specific, Web Based
1188
Initialization of a Resource with an Insecure Default
IncompleteCommon Consequences
Security Scopes Affected:
Other
Potential Impacts:
Varies By Context
Applicable Platforms
All platforms may be affected
https://docs.ovhcloud.com/en/guides/web-cloud/email-and-collaborative-solutions…