Talos Rules 2021-11-25
This release adds and modifies rules in several categories.

Microsoft Vulnerability CVE-2021-42321: A remote code execution vulnerability exists in Microsoft Exchange Server for which exploit code is publicly available.

Rules to detect attacks targeting this vulnerability are included in this release and are identified with GID 1, SIDs 58637 through 58639.

Talos has added and modified multiple rules in the server-other rule sets to provide coverage for emerging threats from these technologies.

Change logs

2021-11-25 21:14:59 UTC

Snort Subscriber Rules Update

Date: 2021-11-25

This is the complete list of rules modified and added in the Sourcefire VRT Certified rule pack for Snort version 2091801.

The format of the file is:

gid:sid <-> Default rule state <-> Message (rule group)

New Rules:


 * 1:58637 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)
 * 1:58638 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)
 * 1:58639 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)

Modified Rules:



2021-11-25 21:14:59 UTC

Snort Subscriber Rules Update

Date: 2021-11-25

This is the complete list of rules modified and added in the Sourcefire VRT Certified rule pack for Snort version 2091800.

The format of the file is:

gid:sid <-> Default rule state <-> Message (rule group)

New Rules:


 * 1:58639 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)
 * 1:58637 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)
 * 1:58638 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)

Modified Rules:



2021-11-25 21:14:59 UTC

Snort Subscriber Rules Update

Date: 2021-11-25

This is the complete list of rules modified and added in the Sourcefire VRT Certified rule pack for Snort version 2091701.

The format of the file is:

gid:sid <-> Default rule state <-> Message (rule group)

New Rules:


 * 1:58637 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)
 * 1:58639 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)
 * 1:58638 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)

Modified Rules:



2021-11-25 21:14:59 UTC

Snort Subscriber Rules Update

Date: 2021-11-25

This is the complete list of rules modified and added in the Sourcefire VRT Certified rule pack for Snort version 2091700.

The format of the file is:

gid:sid <-> Default rule state <-> Message (rule group)

New Rules:


 * 1:58639 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)
 * 1:58638 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)
 * 1:58637 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)

Modified Rules:



2021-11-25 21:14:59 UTC

Snort Subscriber Rules Update

Date: 2021-11-25

This is the complete list of rules modified and added in the Sourcefire VRT Certified rule pack for Snort version 2091601.

The format of the file is:

gid:sid <-> Default rule state <-> Message (rule group)

New Rules:


 * 1:58638 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)
 * 1:58637 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)
 * 1:58639 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)

Modified Rules:



2021-11-25 21:14:59 UTC

Snort Subscriber Rules Update

Date: 2021-11-25

This is the complete list of rules modified and added in the Sourcefire VRT Certified rule pack for Snort version 2091600.

The format of the file is:

gid:sid <-> Default rule state <-> Message (rule group)

New Rules:


 * 1:58637 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)
 * 1:58638 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)
 * 1:58639 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)

Modified Rules:



2021-11-25 21:14:59 UTC

Snort Subscriber Rules Update

Date: 2021-11-25

This is the complete list of rules modified and added in the Sourcefire VRT Certified rule pack for Snort version 2091501.

The format of the file is:

gid:sid <-> Default rule state <-> Message (rule group)

New Rules:


 * 1:58639 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)
 * 1:58637 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)
 * 1:58638 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)

Modified Rules:



2021-11-25 21:14:59 UTC

Snort Subscriber Rules Update

Date: 2021-11-25

This is the complete list of rules modified and added in the Sourcefire VRT Certified rule pack for Snort version 2091401.

The format of the file is:

gid:sid <-> Default rule state <-> Message (rule group)

New Rules:


 * 1:58638 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)
 * 1:58639 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)
 * 1:58637 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)

Modified Rules:



2021-11-25 21:14:59 UTC

Snort Subscriber Rules Update

Date: 2021-11-25

This is the complete list of rules modified and added in the Sourcefire VRT Certified rule pack for Snort version 2091300.

The format of the file is:

gid:sid <-> Default rule state <-> Message (rule group)

New Rules:


 * 1:58637 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)
 * 1:58639 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)
 * 1:58638 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)

Modified Rules:



2021-11-25 21:14:59 UTC

Snort Subscriber Rules Update

Date: 2021-11-25

This is the complete list of rules modified and added in the Sourcefire VRT Certified rule pack for Snort version 2091101.

The format of the file is:

gid:sid <-> Default rule state <-> Message (rule group)

New Rules:


 * 1:58638 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)
 * 1:58639 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)
 * 1:58637 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)

Modified Rules:



2021-11-25 21:14:59 UTC

Snort Subscriber Rules Update

Date: 2021-11-25

This is the complete list of rules modified and added in the Sourcefire VRT Certified rule pack for Snort version 3000.

The format of the file is:

gid:sid <-> Default rule state <-> Message (rule group)

New Rules:


 * 1:58637 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (snort3-server-other.rules)
 * 1:58639 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (snort3-server-other.rules)
 * 1:58638 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (snort3-server-other.rules)

Modified Rules:



2021-11-25 21:14:59 UTC

Snort Subscriber Rules Update

Date: 2021-11-25

This is the complete list of rules modified and added in the Sourcefire VRT Certified rule pack for Snort version 2983.

The format of the file is:

gid:sid <-> Default rule state <-> Message (rule group)

New Rules:


 * 1:58639 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)
 * 1:58637 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)
 * 1:58638 <-> DISABLED <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt (server-other.rules)

Modified Rules:



2021-11-25 21:17:30 UTC

Snort Subscriber Rules Update

Date: 2021-11-25-001

This is the complete list of rules modified and added in the Sourcefire VRT Certified rule pack for Snort version 3.0.3.1.

The format of the file is:

gid:sid <-> Message

New Rules:

* 1:58637 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt
* 1:58638 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt
* 1:58639 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt

Modified Rules:



2021-11-25 21:17:33 UTC

Snort Subscriber Rules Update

Date: 2021-11-25-001

This is the complete list of rules modified and added in the Sourcefire VRT Certified rule pack for Snort version 3.0.3.4.

The format of the file is:

gid:sid <-> Message

New Rules:

* 1:58637 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt
* 1:58638 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt
* 1:58639 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt

Modified Rules:



2021-11-25 21:17:33 UTC

Snort Subscriber Rules Update

Date: 2021-11-25-001

This is the complete list of rules modified and added in the Sourcefire VRT Certified rule pack for Snort version 3.1.0.0.

The format of the file is:

gid:sid <-> Message

New Rules:

* 1:58637 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt
* 1:58638 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt
* 1:58639 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt

Modified Rules:



2021-11-25 21:17:33 UTC

Snort Subscriber Rules Update

Date: 2021-11-25-001

This is the complete list of rules modified and added in the Sourcefire VRT Certified rule pack for Snort version 3.1.0.1.

The format of the file is:

gid:sid <-> Message

New Rules:

* 1:58637 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt
* 1:58638 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt
* 1:58639 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt

Modified Rules:



2021-11-25 21:17:33 UTC

Snort Subscriber Rules Update

Date: 2021-11-25-001

This is the complete list of rules modified and added in the Sourcefire VRT Certified rule pack for Snort version 3.1.1.0.

The format of the file is:

gid:sid <-> Message

New Rules:

* 1:58637 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt
* 1:58638 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt
* 1:58639 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt

Modified Rules:



2021-11-25 21:17:33 UTC

Snort Subscriber Rules Update

Date: 2021-11-25-001

This is the complete list of rules modified and added in the Sourcefire VRT Certified rule pack for Snort version 3.1.3.0.

The format of the file is:

gid:sid <-> Message

New Rules:

* 1:58637 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt
* 1:58638 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt
* 1:58639 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt

Modified Rules:



2021-11-25 21:17:33 UTC

Snort Subscriber Rules Update

Date: 2021-11-25-001

This is the complete list of rules modified and added in the Sourcefire VRT Certified rule pack for Snort version 3.1.4.0.

The format of the file is:

gid:sid <-> Message

New Rules:

* 1:58637 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt
* 1:58638 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt
* 1:58639 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt

Modified Rules:



2021-11-25 21:17:33 UTC

Snort Subscriber Rules Update

Date: 2021-11-25-001

This is the complete list of rules modified and added in the Sourcefire VRT Certified rule pack for Snort version 3.1.5.0.

The format of the file is:

gid:sid <-> Message

New Rules:

* 1:58637 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt
* 1:58638 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt
* 1:58639 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt

Modified Rules:



2021-11-25 21:17:33 UTC

Snort Subscriber Rules Update

Date: 2021-11-25-001

This is the complete list of rules modified and added in the Sourcefire VRT Certified rule pack for Snort version 3.1.7.0.

The format of the file is:

gid:sid <-> Message

New Rules:

* 1:58637 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt
* 1:58638 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt
* 1:58639 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt

Modified Rules:



2021-11-25 21:17:33 UTC

Snort Subscriber Rules Update

Date: 2021-11-25-001

This is the complete list of rules modified and added in the Sourcefire VRT Certified rule pack for Snort version 3.1.9.0.

The format of the file is:

gid:sid <-> Message

New Rules:

* 1:58637 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt
* 1:58638 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt
* 1:58639 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt

Modified Rules:



2021-11-25 21:17:33 UTC

Snort Subscriber Rules Update

Date: 2021-11-25-001

This is the complete list of rules modified and added in the Sourcefire VRT Certified rule pack for Snort version 3.1.11.0.

The format of the file is:

gid:sid <-> Message

New Rules:

* 1:58637 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt
* 1:58638 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt
* 1:58639 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt

Modified Rules:



2021-11-25 21:17:33 UTC

Snort Subscriber Rules Update

Date: 2021-11-25-001

This is the complete list of rules modified and added in the Sourcefire VRT Certified rule pack for Snort version 3.1.15.0.

The format of the file is:

gid:sid <-> Message

New Rules:

* 1:58637 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt
* 1:58638 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt
* 1:58639 <-> SERVER-OTHER Microsoft Exchange Server remote code execution attempt

Modified Rules: