Introduce Password Protected File Analysis (PPFA)

Introduction

This document describes the new Password Protected File Analysis (PPFA) added to the Email Security Appliance (ESA) version 14.X.

Prerequisites

Requirements

Cisco recommends that you have knowledge of ESA concepts and configuration.

Components Used

The information in this document is based on AsyncOS for ESA 14.0 and later.

The information in this document was created from the devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If your network is live, ensure that you understand the potential impact of any command.

Background Information

Previously, the contents of a password protected document or archive file attachment such as PDF, Doc, ZIP and so on, could not be analyzed because the password was unknown.

With the introduction of PPFA, emails which contain password-protected file attachments can be analyzed for malicious activity and data privacy if the password is present in the mail body.

Supported Formats and Language

Here is the list of supported formats:

• PDF
• MS Office File

doc/x 2007-2019 / doc 2002 to 2004

xls/x 2007-2019

ppt/x 2007-2019

• Archive

zip, rar, 7z

Here you can find the list of supported languages: 

Considerations

PPFA is disabled by default.

Password protected file attachments can be analyzed currently only if the password is present in the mail body. The passwords are case sensitive and do not recognize "space". 

A list of up to 5 passwords provided by admin is now supported.

Configuration Steps

Graphical User Interface (GUI)

To configure PPFA from GUI, navigate to Security Service > Scan Behavior > Edit Global Settings > Scanning of Password-protected Attachments > choose to Enable for Inbound Mail traffic/Outbound Mail Traffic or Both >Submit >Commit

Command Line Interface (CLI)

To configure PPFA from CLI, run the command  scanconfig > PROTECTEDATTACHMENTCONFIG > Commit

(ESA_CLI) (SERVICE)> scanconfig

NOTICE: This configuration command has not yet been configured for the current cluster mode (Machine esa1.lab.cisco.com).

What would you like to do?
1. Switch modes to edit at mode "Cluster ESA_BETA_CLUSTER".
2. Start a new, empty configuration at the current mode (Machine esa1.lab.cisco.com).
3. Copy settings from another cluster mode to the current mode (Machine esa1.lab.cisco.com).
[1]>


There are currently 5 attachment type mappings configured to be SKIPPED.

Choose the operation you want to perform:
- NEW - Add a new entry.
- DELETE - Remove an entry.
- SETUP - Configure scanning behavior.
- IMPORT - Load mappings from a file.
- EXPORT - Save mappings to a file.
- PRINT - Display the list.
- CLEAR - Remove all entries.
- SMIME - Configure S/MIME unpacking.
- SAFEPRINT - Configure safeprint settings.
- PROTECTEDATTACHMENTCONFIG - Scan password protected attachments.
- CLUSTERSET - Set how scanconfig is configured in a cluster.
- CLUSTERSHOW - Display how scanconfig is configured in a cluster.
[]> PROTECTEDATTACHMENTCONFIG

Scanning of password-protected attachments for inbound mails: enabled.
Scanning of password-protected attachments for outbound mails: enabled.

Do you want to scan password-protected attachments for inbound mails? y/n [Y]>

Do you want to scan password-protected attachments for outbound mails? y/n [Y]>

Scan password protected attachments configuration unchanged.

Note: By default 5 passwords in the emails body is scanned/extracted.

To increase the maximum number of passwords extracted from an email body, the hidden command "scanconfig > password_list_size" can be used in CLI.  You can configure a maximum of 10 passwords.

Caution: changing this settings to higher value could have performance impact.

(ESA_CLI) (SERVICE)> scanconfig
There are currently 5 attachment type mappings configured to be SKIPPED.

Choose the operation you want to perform:
- NEW - Add a new entry.
- DELETE - Remove an entry.
- SETUP - Configure scanning behavior.
- IMPORT - Load mappings from a file.
- EXPORT - Save mappings to a file.
- PRINT - Display the list.
- CLEAR - Remove all entries.
- SMIME - Configure S/MIME unpacking.
- SAFEPRINT - Configure safeprint settings.
- PROTECTEDATTACHMENTCONFIG - Scan password protected attachments.
- CLUSTERSET - Set how scanconfig is configured in a cluster.
- CLUSTERSHOW - Display how scanconfig is configured in a cluster.
[]> password_list_size

Enter maximum number of passwords to process:
[5]> 1000

Value must be an integer from 1 to 10.

Enter maximum number of passwords to process:
[5]> 10

Password list size is changed.

Troubleshoot and Verification

In this example, the content filter with conditions:

1. attachment content contains "test" and
2. if attachment is password protected

then action is log "!!!!!file is passwordprotected!!!!!!!"

Verification From CLI for Successful Process

a) In CLI from mail_logs you can see:

Wed Feb 24 12:11:59 2022 Info: Start MID 22178287 ICID 122555
Wed Feb 24 12:11:59 2022 Info: MID 22178287 ICID 122555 From: <test@lab.cisco.com>
Wed Feb 24 12:11:59 2022 Info: MID 22178287 ICID 122555 RID 0 To: <test@lab.cisco.com>
Wed Feb 24 12:11:59 2022 Info: MID 22178287 using engine: SPF Verdict Cache using cached verdict
Wed Feb 24 12:11:59 2022 Info: MID 22178287 SPF: helo identity postmaster@[10.0.201.16] None
Wed Feb 24 12:11:59 2022 Info: MID 22178287 using engine: SPF Verdict Cache using cached verdict
Wed Feb 24 12:11:59 2022 Info: MID 22178287 SPF: mailfrom identity test@lab.cisco.com Pass (v=spf1)
Wed Feb 24 12:11:59 2022 Info: MID 22178287 using engine: SPF Verdict Cache using cached verdict
Wed Feb 24 12:11:59 2022 Info: MID 22178287 SPF: pra identity test@lab.cisco.com None headers from
Wed Feb 24 12:11:59 2022 Info: MID 22178287 DMARC: Message from domain lab.cisco.com, DMARC pass (SPF aligned True, DKIM aligned False)
Wed Feb 24 12:11:59 2022 Info: MID 22178287 DMARC: Verification passed
Wed Feb 24 12:11:59 2022 Info: MID 22178287 Message-ID '<4be194cc-4c95-9d15-6528-81a05dc56a66@lab.cisco.com>'
Wed Feb 24 12:11:59 2022 Info: MID 22178287 Subject ppfa test with xls
Wed Feb 24 12:11:59 2022 Info: MID 22178287 SDR: Domains for which SDR is requested: reverse DNS host: Not Present, helo: [10.0.201.16], env-from: lab.cisco, header-from: lab.cisco.com, reply-to: Not Present
Wed Feb 24 12:11:59 2022 Info: MID 22178287 SDR: Consolidated Sender Reputation: Tainted, Threat Category: N/A, Suspected Domain(s) : test@lab.cisco.com. Youngest Domain Age: 4 months 14 days for domain: test@lab.cisco.com
Wed Feb 24 12:11:59 2022 Info: MID 22178287 SDR: Tracker Header : 1+lIjVgkzfH9oTTP+SaBrzZC3Gs6TTYhJbW8D/pjF0eP1U48Yn65OgvVF9VjL6RgIIYi/H6sTg4VSq/leHowYXwYz/1wmYQCDwFFhTTfkLqs/GuqB1ynXwqZRXi2TiSkkHHrJbo+6IUpze9pVWWlgvZomvY7LindREsvoMzHCYesMkNci5Ko0u0m9D1Fz5SoCuVsofk0dbf9rjydhcP4aGxNOTd99njpfkGqdTbZIBv1mBsIS5fRYaDSEEntbcJkuVq3V5ShYK2HZPfKAbzllBxstwYWM0kRe8uIFfiGuCFqDtPaQ1Fb2avNo1MKwLKL
Wed Feb 24 12:11:59 2022 Info: MID 22178287 ready 22082 bytes from <test@lab.cisco.com>
Wed Feb 24 12:11:59 2022 Info: LDAP: Masquerade query LDAP.masquerade MID 22178287 address test@lab.cisco.com to test@lab.cisco.com
Wed Feb 24 12:11:59 2022 Info: LDAP: Masquerade query LDAP.masquerade MID 22178287 address test@lab.cisco.com to test@lab.cisco.com
Wed Feb 24 12:11:59 2022 Info: MID 22178287 attachment 'testfile.xlsx'
Wed Feb 24 12:12:01 2022 Info: MID 22178287 matched all recipients for per-recipient policy test1 in the inbound table
Wed Feb 24 12:12:04 2022 Info: MID 22178287 interim verdict using engine: CASE spam negative
Wed Feb 24 12:12:04 2022 Info: MID 22178287 using engine: CASE spam negative
Wed Feb 24 12:12:04 2022 Info: MID 22178287 interim AV verdict using McAfee ENCRYPTED
Wed Feb 24 12:12:04 2022 Info: MID 22178287 interim AV verdict using Sophos ENCRYPTED
Wed Feb 24 12:12:04 2022 Info: MID 22178287 antivirus encrypted
Wed Feb 24 12:12:04 2022 Info: MID 22178287 AMP file reputation verdict : UNKNOWN(File analysis pending)
Wed Feb 24 12:12:04 2022 Info: MID 22178287 SHA d1e67e9640c598162b891028d967d2e5621d0c1bc1141ef2cec21a0ee1087349 filename testfile.xlsx queued for possible file analysis upload
Wed Feb 24 12:12:04 2022 Info: MID 22178287 using engine: GRAYMAIL negative
Wed Feb 24 12:12:04 2022 Info: MID 22178287 Custom Log Entry: !!!!!!!!!file is passwordprotected!!!!!!!!!
Wed Feb 24 12:12:04 2022 Info: MID 22178287 Unable to safe print the attachment, Filename: testfile.xlsx, Reason: The attachment is encrypted, Action: The attachment is stripped
Wed Feb 24 12:12:04 2022 Info: MID 22178287 rewritten to MID 22178289 by safeprint-all-attachments-strip-unscan filter 'PDF-Safeprint'
Wed Feb 24 12:12:04 2022 Info: Message finished MID 22178287 done

b) From content_scanner logs you can see if the file has been successfully extracted 

Wed Feb 24 12:12:01 2022 Info: PF: MID 22178287 The password-protected file - "testfile.xlsx" is scanned successfully.

c) From amp_logs, You can see that the extracted file is now sent to Advanced Malware Protection (AMP) and File Analysis for analysis.

Tue Mar 16 11:21:03 2022 Info:   File reputation query initiating. File Name = 'testfile.zip', MID = 22194509, File Size = 706376 bytes, File Type = application/zip
Tue Mar 16 11:21:03 2022 Info:   Response received for file reputation query from Cloud. File Name = 'testfile.zip', MID = 22194509, Disposition = FILE UNKNOWN, Malware = None, Analysis Score = 0, sha256 = fb997bf3891f81edc3a4292c22d9fa7fbfc652756eec5e9b7ffd431581694f5b, upload_action = Reco
mmended to send the file for analysis, verdict_source = None
Tue Mar 16 11:21:03 2022 Info:   Compressed/Archive File: sha256 = fb997bf3891f81edc3a4292c22d9fa7fbfc652756eec5e9b7ffd431581694f5b MID = 22194509, Extracted File: File Name = 'testfile.exe', File Type = 'application/x-dosexec', sha256 = f2d2638afb528c7476c9ee8e83ddb20e686b0b05f53f2f966fd9eb
962427f8aa, Disposition = FILE UNKNOWN, Response received from = Cloud, Malware = None, Analysis Score = 0, upload_action = Recommended to send the file for analysis
Tue Mar 16 11:21:04 2022 Info:   File uploaded for preclassification. SHA256: f2d2638afb528c7476c9ee8e83ddb20e686b0b05f53f2f966fd9eb962427f8aa, file name: testfile.exe
Tue Mar 16 11:21:31 2022 Info:   File uploaded for analysis. SHA256: f2d2638afb528c7476c9ee8e83ddb20e686b0b05f53f2f966fd9eb962427f8aa, file name: testfile.exe

d) If the amp_logs are in Debug level, you can see more information related to password protected file:

 Tue Mar 16 11:21:03 2022  Unarchive:-  AMP-DEBUG: amp_supported_file_mime: Supported mime : application/zip
 Tue Mar 16 11:21:03 2022  Unarchive:-  AMP-DEBUG: _amp_unarchv_mem2file - in_buf=0x96682000, size=706376, ctext=0x0, parent=0x0
 Tue Mar 16 11:21:03 2022  Unarchive:-  AMP-DEBUG: password is Cisco
Tue Mar 16 11:21:03 2022  Unarchive:-  AMP-DEBUG: amp_context_create - ctext=0x96610ec0
 Tue Mar 16 11:21:03 2022  Unarchive:-  AMP-DEBUG: archive size = 706376, max archive size=14127520
 Tue Mar 16 11:21:03 2022  Unarchive:-  AMP-DEBUG: password is Cisco
Tue Mar 16 11:21:03 2022  Unarchive:-  AMP-DEBUG: amp_context_create - ctext=0x96610ec0
 Tue Mar 16 11:21:03 2022  Unarchive:-  AMP-DEBUG: archive size = 706376, max archive size=14127520
 Tue Mar 16 11:21:03 2022  Unarchive:-  AMP-DEBUG: amp_make_dated_dir - path=/data/tmp/amp/2022_03_16
 Tue Mar 16 11:21:03 2022  Unarchive:-  AMP-DEBUG: update_full_pathname entered - path=/data/tmp/amp/2022_03_16, filename=testfile.exe, suffix=#amp_1_1615911663
 Tue Mar 16 11:21:03 2022  Unarchive:-  AMP-DEBUG: update_full_pathname - archive_entry_set_pathname, /data/tmp/amp/2022_03_16/testfile.exe#amp_1_1615911663
 Tue Mar 16 11:21:03 2022  Unarchive:-  AMP-DEBUG: amp_queue_entry_insert - ctext=0x96610ec0, parent=0x0, pathname=/data/tmp/amp/2022_03_16/testfile.exe#amp_1_1615911663
 Tue Mar 16 11:21:03 2022  Unarchive:-  AMP-DEBUG: _amp_unarchv_file2file - ctext=0x96610ec0, parent_qe=0x9666a2e0, filename=/data/tmp/amp/2022_03_16/testfile.exe#amp_1_1615911663
 Tue Mar 16 11:21:03 2022  Unarchive:-  AMP-DEBUG: Unsupported file type: application/x-dosexec
 Tue Mar 16 11:21:03 2022  Unarchive:-  AMP-DEBUG: _amp_unarchv_mem2file - in_buf=0x97284000, size=1096080, ctext=0x96610ec0, parent=0x9666a2e0
 Tue Mar 16 11:21:03 2022  Unarchive:-  AMP-DEBUG: _amp_unarchv_mem2file - decode depth (0)
 Tue Mar 16 11:21:03 2022  Unarchive:-  AMP-DEBUG: _amp_unarchv_file2file - archive cumulative size=1096080  no.of files=1
 Tue Mar 16 11:21:03 2022   AMPPyrex:-   AMP-INFO: set_analysis_params do_sandbox=0, do_analysis=0,file_mime=application/zip, file priortiy=0 preclass_type=2
Tue Mar 16 11:21:03 2022   AMPPyrex:-   AMP-INFO: set_analysis_params do_sandbox=1, do_analysis=1,file_mime=application/x-dosexec, file priortiy=0 preclass_type=4
Tue Mar 16 11:21:03 2022 AMPCloudIF:-  AMP-DEBUG: AMP Query Request, FileType[0] SHA256[fb997bf3891f81edc3a4292c22d9fa7fbfc652756eec5e9b7ffd431581694f5b]

......

ue Mar 16 11:21:03 2022  CloudPool:-  AMP-DEBUG: cb in callback_thread
Tue Mar 16 11:21:03 2022 AMPCloudIF:-  AMP-DEBUG: AMP Query Response[Cloud], SHA256[fb997bf3891f81edc3a4292c22d9fa7fbfc652756eec5e9b7ffd431581694f5b], disposition[1] score[0] score_tg[0] score_type[0] SpyName[] action[1]
 Tue Mar 16 11:21:03 2022 CacheUtils:-  AMP-DEBUG: Found SHA256: - SHA256::fb997bf3891f81edc3a4292c22d9fa7fbfc652756eec5e9b7ffd431581694f5b
Tue Mar 16 11:21:03 2022  CloudPool:-  AMP-DEBUG: imcloud callback thread going to sleep
Tue Mar 16 11:21:03 2022 VRTCloudIF:-  AMP-DEBUG: Status List, Server Response HTTP code:[200]
Tue Mar 16 11:21:03 2022 CacheUtils:-  AMP-DEBUG: Found SHA256: - SHA256::f2d2638afb528c7476c9ee8e83ddb20e686b0b05f53f2f966fd9eb962427f8aa
Tue Mar 16 11:21:03 2022 VRTCloudIF:-  AMP-DEBUG: File SHA256[f2d2638afb528c7476c9ee8e83ddb20e686b0b05f53f2f966fd9eb962427f8aa] pri - [0] is enqueued to vrt
 Tue Mar 16 11:21:03 2022  Unarchive:-  AMP-DEBUG: amp_entry_preserve_file - ctext=0x96610ec0, pathname=/data/tmp/amp/2022_03_16/testfile.exe#amp_1_1615911663
 Tue Mar 16 11:21:03 2022  Unarchive:-  AMP-DEBUG: amp_entry_preserve_file - preserved  pathname=/data/tmp/amp/2022_03_16/testfile.exe#amp_1_1615911663
 Tue Mar 16 11:21:03 2022  Unarchive:-  AMP-DEBUG: amp_context_delete - ctext=0x96610ec0
 Tue Mar 16 11:21:03 2022  Unarchive:-  AMP-DEBUG: amp_queue_entry_free - entry=0x9666a2e0, pathname=/data/tmp/amp/2022_03_16/testfile.exe#amp_1_1615911663 file_mime =application/x-dosexec, preserved=1
 Tue Mar 16 11:21:03 2022  Unarchive:-  AMP-DEBUG: amp_context_free - ctext=0x96610ec0
 Tue Mar 16 11:21:03 2022     AMPRPC:-   AMP-INFO: Adjusted verdict - {'file_type': 'application/zip', 'file_name': 'testfile.zip', 'verdict_source': None, 'spyname': '', 'custom_threshold': None, 'unscan_category': None, 'category': 'amp', 'original_verdict': 'FILE UNKNOWN', 'analysis_statu
s': 1, 'analysis_score': 0, 'score': 0, 'sha256': 'fb997bf3891f81edc3a4292c22d9fa7fbfc652756eec5e9b7ffd431581694f5b', 'verdict_str': 'FILE UNKNOWN', 'uploaded': False, 'verdict_from': 'Cloud', 'xid': 22194509, 'verdict_num': 1, 'blacklisted': False, 'extract_file_verdict_list': deque([{'c
ategory': 'amp', 'uploaded': True, 'original_verdict': 'FILE UNKNOWN', 'analysis_status': 4, 'verdict_num': 1, 'analysis_score': 0, 'file_type': 'application/x-dosexec', 'file_name': 'testfile.exe', 'verdict_source': None, 'verdict_from': 'Cloud', 'spyname': '', 'score': 0, 'unscan_category'
: None, 'upload_reason': None, 'sha256': 'f2d2638afb528c7476c9ee8e83ddb20e686b0b05f53f2f966fd9eb962427f8aa', 'verdict_str': 'FILE UNKNOWN', 'analysis_action': 1, 'blacklisted': False}]), 'analysis_action': 1, 'verdict': 'FILE UNKNOWN', 'error': None}
Tue Mar 16 11:21:03 2022 VRTCloudIF:-  AMP-DEBUG: Set curl options URL[https://tg1-clean.lab.cisco.com/csa/v3/run/file?apikey=qg8ecq3n5c9ld4inbps783g263&async=true&classify=true], Trust Store[/data/fire_amp/db/preserve/private_cert.pem]
 Tue Mar 16 11:21:03 2022 VRTCloudIF:-  AMP-DEBUG: {"message":"Success","hash":"f2d2638afb528c7476c9ee8e83ddb20e686b0b05f53f2f966fd9eb962427f8aa","base_url":"https://tg1-clean.lab.cisco.com","entitlement_buffer_info":{"used":0,"available":true,"available_on":"2022-03-16T16:21:03Z"},"anal
yzing":"unknown","sample":"d5c8d83543d92c0cc428d6377d1c665d","query":"https://tg1-clean.lab.cisco.com/csa/v3/report?sample=d5c8d83543d92c0cc428d6377d1c665d"}
 Tue Mar 16 11:21:03 2022 VRTCloudIF:-  AMP-DEBUG:  File upload successful filename testfile.exe
 Tue Mar 16 11:21:03 2022 CacheUtils:-  AMP-DEBUG: Found SHA256: - SHA256::f2d2638afb528c7476c9ee8e83ddb20e686b0b05f53f2f966fd9eb962427f8aa
Tue Mar 16 11:21:03 2022 VRTCloudIF:-  AMP-DEBUG: File SHA256[f2d2638afb528c7476c9ee8e83ddb20e686b0b05f53f2f966fd9eb962427f8aa], file mime[application/x-dosexec], upload priority[High] successfully uploaded to the VRT server.
Tue Mar 16 11:21:03 2022   AMPPyrex:-   AMP-INFO: Upload SHA[f2d2638afb528c7476c9ee8e83ddb20e686b0b05f53f2f966fd9eb962427f8aa] runid=0 sampleid = timestamp=1615911663
Tue Mar 16 11:21:17 2022   AMPPyrex:-  AMP-DEBUG: AMP Extraction monitoring thread entering into sleep. Thread pool length=19 free pool size=1

Verification From GUI for Successful Process

Navigate to Message Tracking and filter the message ID.

Verification From CLI for Failed Process

Condition: incorrect password or password not found.

a) From mail_logs in CLI 

Wed Feb 24 12:24:40 2022 Info: MID 22178297 ICID 122563 From: <test@lab.cisco.com>
Wed Feb 24 12:24:40 2022 Info: MID 22178297 ICID 122563 RID 0 To: <test2@lab.cisco.com>
Wed Feb 24 12:24:40 2022 Info: MID 22178297 using engine: SPF Verdict Cache using cached verdict
Wed Feb 24 12:24:40 2022 Info: SPF Verdict Cache cache status: hits = 10, misses = 531, expires = 318, adds = 531, seconds saved = 0.04, total seconds = 9.69
Wed Feb 24 12:24:40 2022 Info: MID 22178297 SPF: helo identity postmaster@[10.0.201.16] None
Wed Feb 24 12:24:40 2022 Info: MID 22178297 using engine: SPF Verdict Cache using cached verdict
Wed Feb 24 12:24:40 2022 Info: MID 22178297 SPF: mailfrom identity test@lab.cisco.com Pass (v=spf1)
Wed Feb 24 12:24:40 2022 Info: MID 22178297 using engine: SPF Verdict Cache using cached verdict
Wed Feb 24 12:24:40 2022 Info: MID 22178297 SPF: pra identity test@lab.cisco.com None headers from
Wed Feb 24 12:24:40 2022 Info: MID 22178297 DMARC: Message from domain lab.cisco.com, DMARC pass (SPF aligned True, DKIM aligned False)
Wed Feb 24 12:24:40 2022 Info: MID 22178297 DMARC: Verification passed
Wed Feb 24 12:24:40 2022 Info: MID 22178297 Message-ID '<825ab100-3066-e35e-148e-9ea08cb2fb28@lab.cisco.com>'
Wed Feb 24 12:24:40 2022 Info: MID 22178297 Subject ppfa test without password
Wed Feb 24 12:24:40 2022 Info: MID 22178297 SDR: Domains for which SDR is requested: reverse DNS host: Not Present, helo: [10.0.201.16], env-from: lab.cisco.com, header-from: lab.cisco.com, reply-to: Not Present
Wed Feb 24 12:24:40 2022 Info: MID 22178297 SDR: Consolidated Sender Reputation: Tainted, Threat Category: N/A, Suspected Domain(s) : test@lab.cisco.com. Youngest Domain Age: 4 months 14 days for domain: test@lab.cisco.com
Wed Feb 24 12:24:40 2022 Info: MID 22178297 SDR: Tracker Header : jiOYjEFgtyhTbL9t0GE5obyJYv3d6lj/sYLgchp5eutSz6X67FGFv3IHCBbU5wQBlYXe8Bv/r+uhxP6VIAXvyXSt35AAGc5hkANFBHB0v/PJzmLg4sd2yacAozybm9ITPJKTdj+4cQtIrgZxBJtCuBoBQ9Y4v00rdaaYT15VZ3CLjypIvVIZeImiTGR1OwocHluoZrdecXFIT3Lo9lTBsJVPbIkyI3AU0Z82nQPgkCsp8CVAQYYlQXqd7ObrcFIsfX6NHZ+Z22kXaRlBd7FMk4PJ6u8X3R9B1vP+bJoM5Cxx15ZHNkgD49u8PJT2ags4
Wed Feb 24 12:24:40 2022 Info: MID 22178297 ready 22089 bytes from <test@lab.cisco.com>
Wed Feb 24 12:24:40 2022 Info: LDAP: Masquerade query LDAP.masquerade MID 22178297 address test@lab.cisco.com to test@lab.cisco.com
Wed Feb 24 12:24:40 2022 Info: ICID 122563 close
Wed Feb 24 12:24:40 2022 Info: LDAP: Masquerade query LDAP.masquerade MID 22178297 address test@lab.cisco.com to test@lab.cisco.com
Wed Feb 24 12:24:40 2022 Info: MID 22178297 attachment 'testfile.xlsx'
Wed Feb 24 12:24:42 2022 Info: MID 22178297 was marked unscannable due to extraction failures. Reason: The password protected attachment 'testfile.xlsx' could not be scanned successfully.
Wed Feb 24 12:24:42 2022 Warning: MID 22178297: scanning error (name='testfile.xlsx', type=document/xls): Extraction failure of password protected attachment
Wed Feb 24 12:24:42 2022 Info: MID 22178297 matched all recipients for per-recipient policy test1 in the inbound table
Wed Feb 24 12:24:46 2022 Info: MID 22178297 interim verdict using engine: CASE spam negative
Wed Feb 24 12:24:46 2022 Info: MID 22178297 using engine: CASE spam negative
Wed Feb 24 12:24:46 2022 Info: MID 22178297 interim AV verdict using McAfee ENCRYPTED
Wed Feb 24 12:24:46 2022 Info: MID 22178297 interim AV verdict using Sophos ENCRYPTED
Wed Feb 24 12:24:46 2022 Info: MID 22178297 antivirus encrypted
Wed Feb 24 12:24:46 2022 Info: MID 22178297 AMP file reputation verdict : UNKNOWN
Wed Feb 24 12:24:46 2022 Info: MID 22178297 using engine: GRAYMAIL negative
Wed Feb 24 12:24:46 2022 Info: MID 22178297 Unable to safe print the attachment, Filename: testfile.xlsx, Reason: The attachment is encrypted, Action: The attachment is stripped
Wed Feb 24 12:24:46 2022 Info: MID 22178297 rewritten to MID 22178298 by safeprint-all-attachments-strip-unscan filter 'PDF-Safeprint'
Wed Feb 24 12:24:46 2022 Info: Message finished MID 22178297 done

b) In content_scanner you can see: 

Wed Feb 24 12:24:42 2022 Info: PF: MID 22178297 Failed to open document - 'testfile.xlsx' because it is password protected.

Verification From GUI for Failed Process

a)  From GUI in Message Tracking, filter for Message ID

Nested password protected files

Nested password protected files cannot be extracted. Currently this is not supported.

You can see this error in mail_logs

Sun Nov 22 21:09:31 2022 Info: MID 19597596 attachment 'testfile.zip'
Sun Nov 22 21:09:31 2022 Info: ICID 465893 close
Sun Nov 22 21:09:41 2022 Info: MID 19597596 was marked unscannable due to extraction failures. Reason: The attachment could not be decrypted for scanning.

View Status

Use "ppfastats" command in CLI to view the summary of the messages that had password protected attachments and were scanned by ESA.

Note:  ppfastats is a hidden command.

(Machine esa1.lab.cisco.com)> ppfastats

Incoming PPFA Statistics:
Total number of Password Protected Attachments : 425
Total number of Sucessfully scanned Password Protected Attachments : 386
Total number of Protected PDF Attachments : 136
Total number of Sucessfully scanned PDF Attachments : 136
Total number of Protected Office Attachments (XLS, PPT, DOC) : 36
Total number of Sucessfully scanned Office Attachments : 36
Total number of Protected Archive Attachments : 253
Total number of Sucessfully scanned Archive Attachments (ZIP) : 214

Outgoing PPFA Statistics:
PPFA Statistics data not available for Outgoing Mails.

Related Information

• User Guide for AsyncOS 14.3 for Cisco Secure Email Cloud Gateway - Cisco