Enterprise Protection S/MIME Opaque Signature Attachment Scanning Bypass

Enterprise Protection S/MIME Opaque Signature Attachment Scanning Bypass, CVE-2024-10635

Advisory ID: PFPT-SA-2025-0002

Enterprise Protection contains a vulnerability in attachment scanning that allows an unauthenticated attacker to send an email with an S/MIME attachment that is signed with an opaque signature to bypass attachment scanning controls and have the message to delivered to the user's inbox in violation of the scanning policy. This vulnerability is due to improper input validation on the email attachment since the S/MIME attachment is only signed and is still in plain-text.

Proofpoint On-Demand Customers

No action is required. Applicable fixes have already been deployed by Proofpoint.

Proofpoint On-Premises Customers

If you are running a supported version that is configured to deploy releases automatically, no action is required.  Applicable fixes have been automatically deployed.

For on-premise environments that are configured to manually apply releases, install the applicable release as noted below.

If you are running an end of life release please upgrade to a supported release as soon as possible.

For any questions or concerns please contact Proofpoint Support.

Vulnerability Information

This vulnerability is identified by CVE-2025-0431. Proofpoint has released patches to address this issue.

This vulnerability has been assigned a CVSS score of 6.1 - MEDIUM:

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:P/RL:U/RC:R

Fixed Software

Proofpoint has released fixed software versions:

8.18.6 patch 5110
8.20.6 patch 5134
8.21.0 patch 5112
8.22.0 all patch levels (8.22.0 is unaffected by the vulnerability)

All versions below the listed patch levels are vulnerable, including end-of-life software. The fixed software versions are now available through the customer support portal.

URL

https://www.proofpoint.com/us/security/security-advisories/pfpt-sa-2025-0002

Revision History

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