VBN File Format

VBN file format V1 (Windows - SEP 11)

VBN file format V2 (Windows - SEP 12 +)

VBN Metadata

Offset Length Field Description
0 4 Size Size of the VBN Metadata section, 0xe5c
4 384 Description FQP of Quarantine File
388 984 Log Line Information on event.
1372 4 Data Type Value which can describe the subsequent data. (0x1 = No dates, 0x2 = Dates)
1376 4 Record ID VBin ID/VBN Name
1380 8 Date Created Indicates a time of creation of object on the file system. (Windows Filetime)
1388 8 Date Accessed Indicates a time of last access of an object. (Windows Filetime)
1396 8 Date Modified Indicates a time of last modification of content. (Windows Filetime)
1404 4 Data Type Value which can describe the subsequent data. (0x0 = No storage info, 0x2 = Storage info
1408 484 Unknown Will require further investigation as to the purpose of this entry.
1892 48 Storage Name Where threat was found (FileSystem/InternetMail/LotusNotes/MicrosoftExchange)
1940 4 Storage Instance ID Will require further investigation as to the purpose of this entry.
1944 384 Storage Key Will require further investigation as to the purpose of this entry.
2328 4 Data Type Value which can describe the subsequent data.
2332 4 Unknown Will require further investigation as to the purpose of this entry.
2336 8 Unknown Will require further investigation as to the purpose of this entry.
2344 4 Data Type Value which can describe the subsequent data.
2348 4 Quarantine Data Size Size of Quarantined Data (bytes)
2352 4 Date Accessed Indicates a time of last access of an object. (Unix: 32 bit Hex)
2356 4 Date Modified Indicates a time of last modification of content. (Unix: 32 bit Hex)
2360 4 Date Created Indicates a time of creation of object on the file system. (Unix: 32 bit Hex)
2364 4 VBin Time Time data was quarantined. (Unix: 32 bit Hex)
2368 8 Unknown Will require further investigation as to the purpose of this entry.
2376 16 Unique ID Unique GUID
2392 260 Unknown Will require further investigation as to the purpose of this entry.
2652 4 Unknown Will require further investigation as to the purpose of this entry.
2656 4 Record Type 0x0 = Hybrid, 0x1 = Meta, 0x2 = Quarantine
2660 4 Quarantine Session ID Name of subfolder where VBN is stored
2664 4 Remediation Type Type of remediation

0 None
2000 Registry
2001 File
2002 Process
2003 Batch File
2004 INI File
2005 Service
2006 Infected File
2007 COM Object
2008 Host File Entry
2009 Directory
2010 Layered Service Provider
2011 Internet Browser Cache
2668 4 Unknown Will require further investigation as to the purpose of this entry.
2672 4 Unknown Will require further investigation as to the purpose of this entry.
2676 4 Unknown Will require further investigation as to the purpose of this entry.
2680 4 Unknown Will require further investigation as to the purpose of this entry.
2684 4 Unknown Will require further investigation as to the purpose of this entry.
2688 4 Unknown Will require further investigation as to the purpose of this entry.
2692 4 Unknown Will require further investigation as to the purpose of this entry.
2696 768 Wide Description FQP of Quarantine File (Unicode)
3464 212 Unknown Will require further investigation as to the purpose of this entry.

VBN Metadata

Offset Length Field Description
0 4 Size Size of the VBN Metadata section, 0x1290
4 384 Description FQP of Quarantine File
388 2048 Log Line Information on event.
2436 4 Data Type Value which can describe the subsequent data. (0x1 = No dates, 0x2 = Dates)
2440 4 Record ID VBin ID/VBN Name
2444 8 Date Created Indicates a time of creation of object on the file system. (Windows Filetime)
2452 8 Date Accessed Indicates a time of last access of an object. (Windows Filetime)
2460 8 Date Modified Indicates a time of last modification of content. (Windows Filetime)
2468 4 Data Type Value which can describe the subsequent data. (0x0 = No storage info, 0x2 = Storage info
2472 484 Unknown Will require further investigation as to the purpose of this entry.
2956 48 Storage Name Where threat was found (FileSystem/InternetMail/LotusNotes/MicrosoftExchange)
3004 4 Storage Instance ID Will require further investigation as to the purpose of this entry.
3008 384 Storage Key Will require further investigation as to the purpose of this entry.
3392 4 Data Type Value which can describe the subsequent data.
3396 4 Unknown Will require further investigation as to the purpose of this entry.
3400 8 Unknown Will require further investigation as to the purpose of this entry.
3408 4 Data Type Value which can describe the subsequent data.
3412 4 Quarantine Data Size Size of Quarantined Data (bytes)
3416 4 Date Accessed Indicates a time of last access of an object. (Unix: 32 bit Hex)
3420 4 Unknown Will require further investigation as to the purpose of this entry.
3424 4 Date Modified Indicates a time of last modification of content. (Unix: 32 bit Hex)
3428 4 Unknown Will require further investigation as to the purpose of this entry.
3432 4 Date Created Indicates a time of creation of object on the file system. (Unix: 32 bit Hex)
3436 4 Unknown Will require further investigation as to the purpose of this entry.
3440 4 VBin Time Time data was quarantined. (Unix: 32 bit Hex)
3444 4 Unknown Will require further investigation as to the purpose of this entry.
3448 4 Unknown Will require further investigation as to the purpose of this entry.
3452 16 Unique ID Unique GUID
3468 260 Unknown Will require further investigation as to the purpose of this entry.
3728 4 Unknown Will require further investigation as to the purpose of this entry.
3732 4 Record Type 0x0 = Hybrid, 0x1 = Meta, 0x2 = Quarantine
3736 4 Quarantine Session ID Name of subfolder where VBN is stored
3740 4 Remediation Type Type of remediation

0 None
2000 Registry
2001 File
2002 Process
2003 Batch File
2004 INI File
2005 Service
2006 Infected File
2007 COM Object
2008 Host File Entry
2009 Directory
2010 Layered Service Provider
2011 Internet Browser Cache
3744 4 Unknown Will require further investigation as to the purpose of this entry.
3748 4 Unknown Will require further investigation as to the purpose of this entry.
3752 4 Unknown Will require further investigation as to the purpose of this entry.
3756 4 Unknown Will require further investigation as to the purpose of this entry.
3760 4 Unknown Will require further investigation as to the purpose of this entry.
3764 4 Unknown Will require further investigation as to the purpose of this entry.
3768 4 Unknown Will require further investigation as to the purpose of this entry.
3772 768 Wide Description FQP of Quarantine File (Unicode)
4540 212 Unknown Will require further investigation as to the purpose of this entry.

The Record Type determines what comes next.

Record Type 0
The following sections are XORed with 0x5A.

Record Type 1

Record Type 2
The following sections are XORed with 0x5A.

QData Location (Optional)

Offset Length Field Description
0 8 Header QData location header, 00000006aaaa20ce
8 8 Quarantine Data Offset Offset to start of quarantine data
16 8 QData Location Size Size of QData Location
24 4 QData Info Size Size of QData Info from end of quarantine data to EOF
28 Data Offset - 28 Unknown Will require further investigation as to the purpose of this entry.

Quarantine Data

Offset Length Field Description
0 Varies Data Quarantine data

QData Info (Optional)

Offset Length Field Description
0 8 Header QData info header
8 8 QData Info Size Size of QData info
16 QData Info Size - 16 QData Additional information about the quarantine data

Quarantine Metadata

The quarantine metadata appears to be in ASN.1 format. It is comprised of a series of tags.

Code Value Length Extra Data
0x01 1 None
0x0A 1 None
0x03 4 None
0x06 4 None
0x04 8 None
0x07 4 NUL-terminated ASCII String (of length controlled by dword following 0x07 code)
0x08 4 NUL-terminated Unicode String (of length controlled by dword following 0x08 code)
0x09 4 Container (of length controlled by dword following 0x09 code)
0x0F 16 None
0x10 16 None

Quarantine Metadata

Offset Length Field Description
0 8 QM Header Header is always 0000000000000000
8 8 QM Header Size Size, in bytes, of the QM header
16 8 QM Size Size, in bytes, of the QM
24 8 QM Size + Header Size Size, in bytes, of the QM and header
32 8 End of QM to End of VBN Size, in bytes, from end of QM to end of VBN
40 QM Size Quarntine Metadata Quarantine Metadata

The quarantine metadata appears to be in ASN.1 format. It is comprised of a series of tags.

ASN.1 Tags

Code Value Length Extra Data
0x01 1 None
0x0A 1 None
0x03 4 None
0x06 4 None
0x04 8 None
0x07 4 NUL-terminated ASCII String (of length controlled by dword following 0x07 code)
0x08 4 NUL-terminated Unicode String (of length controlled by dword following 0x08 code)
0x09 4 Container (of length controlled by dword following 0x09 code)
0x0F 16 None
0x10 16 None

The Tag determines what comes next.

0x03 Quarantine Hash

0x06 Unknown

Quarantine Hash

Offset Length Field Description
0 1 Tag1 0x03
1 4 Tag1 Value Tag1 Value
5 1 Tag2 Tag2
6 1 Tag2 Value Tag2 Value (value can be 0x00 or 0x01)
7 1 Tag3 (Optional) Tag3 (if Tag2 Value is 0x01, Tag3 is 0x08
8 4 SHA1 Hash Length (Optional) Length of SHA1 (if Tag3 is 0x08, data will be present)
12 SHA1 Hash Length SHA1 (Optional) SHA1 of quarantine data
94 1 Tag4 (Optional) Tag4, always 0x03
95 4 Tag4 Value (Optional) Tag4 Value
99 1 Tag5 (Optional) Tag5, always 0x03
100 4 Tag5 Value (Optional) Tag5 Value
104 1 Tag6 (Optional) Tag6, always 0x09
105 4 Quarantine Data Size Length (Optional) Length of quarantine data size
109 Quarantine Data Size Length Quarantine Data Size 2 (Optional) Size of quarantine data

Quarantine SDDL (Optional)

(may not be present)

Offset Lenght Field Description
0 1 Tag7 Tag7, always 0x08
1 4 Security Descriptor Size Variable length
5 Security Descriptor Size Security Descriptor Security descriptor of file
Varies 1 Tag8 Tag8
Varies 4 Tag8 Value Tag8 Value
Varies 1 Tag9 Tag9
Varies 8 Quarantine Data Size 3 Size of quarntine data

If the Quarantine SDDL tag is not present, there can be two additional structures included with the quarantine data.

Unknown (Optional)

If the Quarantine Data Size in VBN Metadata is Smaller than the Quarantine Data Size in Quarantine Info, this structure will be present.

Offset Lenght Field Description
0 1 Tag ASN.1 tag, 0x09
1 4 Chunk Size Variable length
5 8 Unknown Will require further investigation as to the purpose of this entry. (XORed with A5)
13 4 Unknown Data Size Size of unknown data (XORed with A5)
17 8 Unknown Will require further investigation as to the purpose of this entry. (XORed with A5)
25 Unknown Data Size Unknown Will require further investigation as to the purpose of this entry. (XORed with A5)
Varies 8 Unknown Will require further investigation as to the purpose of this entry. (XORed with A5)
Varies 4 Quarantine Data Size Size of quarantined data (XORed with A5)
Varies 8 Unknown Will require further investigation as to the purpose of this entry. (XORed with A5)
Varies Chunk Size Data Quarantine data (XORed with A5)

Quarantine Data (Optional)

The quarantine data is broken into chunks of data XORed with 0xA5. This continues until the last chunk divider.

Offset Lenght Field Description
0 1 Tag ASN.1 tag, 0x09
1 4 Chunk Size Variable length
5 Chunk Size Data Quarantine data (XORed with A5)

Attribute (Optional)

The followinf data is XORed with A5

Offset Lenght Field Description
Varies 8 Attribute Data Type (Optional) 0x02 = $EA, 0x04 = $DATA, 0x07 = $OBJECT_ID
Varies 8 Attribute Data Size (Optional) Size of attribute data
Varies 4 Attribute Name Size (Optional) Size of attribute name field
Varies Attribute Name Size Attribute Name (Optional) Name of attribute
Varies Attribute Data Size Attribute Data (Optional) Data, varies by type

The Unknown appears to be in ASN.1 format. It is comprised of a series of tags.

ASN.1 Tags

Code Value Length Extra Data
0x01 1 None
0x0A 1 None
0x03 4 None
0x06 4 None
0x04 8 None
0x07 4 NUL-terminated ASCII String (of length controlled by dword following 0x07 code)
0x08 4 NUL-terminated Unicode String (of length controlled by dword following 0x08 code)
0x09 4 Container (of length controlled by dword following 0x09 code)
0x0F 16 None
0x10 16 None