Customers Email message containing badly formatted CSS causes Denial of Service in Spam Engine

Customers Email message containing badly formatted CSS causes Denial of Service in Spam Engine, CVE-2021-39304

Advisory ID: PFPT-SA-2021-0007

A Cascading Style Sheets processing vulnerability in the Spam Engine may allow an attacker to deliver malicious emails causing the Spam Engine to become unresponsive. A successful attack may result in a disruption of email delivery.  Version 8.12.0-2107140000 of Spam Engine and later affected by this vulnerability.  A fix was delivered in version 8.12.0-20210809.

Vulnerability Information

This vulnerability is identified by CVE-2021-39304.  Proofpoint has released fixes to address this issue.

The vulnerability has been assigned a CVSS score of 6.7:

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

Proofpoint on-premises Customers Fixed Software

Proofpoint has released fixes in Spam Engine 20210809.

Proofpoint on Demand Customers

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

Proofpoint on-premises Customers

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

No action is required for Enterprise Protection (PPS) Hardware and Virtual Appliance customers, running supported versions that are configured to deploy releases automatically. Applicable fixes have been automatically deployed.

No mail flow will be interrupted while updates are applied.

For any questions or concerns, please contact Proofpoint Support.

URL

https://www.proofpoint.com/us/security/security-advisories/pfpt-sa-2021-0007

Revision History

Version Description Section Date
1.0 Initial release   Oct 11, 2021

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