A list of CyberChef recipes
For background see Twitter #cyberchef or https://bitofhex.com/2018/05/29/cyberchef/
Full credit to @GCHQ for producing the tool. See: https://gchq.github.io/CyberChef/
Recipe 1: Extract base64, raw inflate & beautify
Recipe 4: Group Policy Preference Password Decryption
Recipe 5: Using Loops and Labels
Recipe 6: Google ei Timestamps
Recipe 7: Multi-stage COM scriplet to x86 assembly
Recipe 8: - Extract hexadecimal, convert to hexdump for embedded PE file
Recipe 9 - Reverse strings, character substitution, from base64
Recipe 10 - Extract object from Squid proxy cache
Recipe 11 - Extract GPS Coordinates to Google Maps URLs
Recipe 12 - Big Number Processing
Recipe 13 - Parsing DNS PTR records with Registers
Recipe 14 - Decoding POSHC2 executables
Recipe 15 - Parsing $MFT $SI Timestamps
Recipe 16 - Decoding PHP gzinflate and base64 webshells
Recipe 17 - Extracting shellcode from a Powershell Meterpreter Reverse TCP Script
Recipe 18 - Recycle Bin Parser with Subsections and Merges
Recipe 19 - Identify Obfuscated Base64 with Regular Expression Highlighting
Recipe 20 - Using Yara rules with deobfuscated malicious scripts
A very common scenario: extract Base64, inflate, beautify the code. You may need to then do further processing or dynamic analysis depending on the next stage.
Filename: ahack.bat
Zipped File: cc9c6c38840af8573b8175f34e5c54078c1f3fb7c686a6dc49264a0812d56b54_183SnuOIVa.bin.gz
Sample: SHA256 cc9c6c38840af8573b8175f34e5c54078c1f3fb7c686a6dc49264a0812d56b54
[{"op":"Regular expression","args":["User defined","[a-zA-Z0-9+/=]{30,}",true,true,false,false,false,false,"List matches"]},{"op":"From Base64","args":["A-Za-z0-9+/=",true]},{"op":"Raw Inflate","args":[0,0,"Adaptive",false,false]},{"op":"Generic Code Beautify","args":[]}]
CyberChef won't be able to handle all types of Invoke-Obfuscation, but here is one that can be decoded.
Filename: Acknowledgement NUT-95-52619.eml
Zipped File: 1240695523bbfe3ed450b64b80ed018bd890bfa81259118ca2ac534c2895c835.bin.gz
Sample: SHA256 1240695523bbfe3ed450b64b80ed018bd890bfa81259118ca2ac534c2895c835
[{"op":"Find / Replace","args":[{"option":"Regex","string":"\\^|\\\\|-|_|\\/|\\s"},"",true,false,true,false]},{"op":"Reverse","args":["Character"]},{"op":"Generic Code Beautify","args":[]},{"op":"Find / Replace","args":[{"option":"Simple string","string":"http:"},"http://",true,false,true,false]},{"op":"Extract URLs","args":[false]},{"op":"Defang URL","args":[true,true,true,"Valid domains and full URLs"]}]
Malware and scripts often use Charcode to represent characters in order to evade from AV and EDR solutions. CyberChef eats this up.
Filename: 3431818-f71f60d10b1cbe034dc1be242c6efa5b9812f3c6.zip
Source: https://gist.github.com/jonmarkgo/3431818
[{"op":"Regular expression","args":["User defined","([0-9]{2,3}(,\\s|))+",true,true,false,false,false,false,"List matches"]},{"op":"From Charcode","args":["Comma",10]},{"op":"Regular expression","args":["User defined","([0-9]{2,3}(,\\s|))+",true,true,false,false,false,false,"List matches"]},{"op":"From Charcode","args":["Space",10]}]
When a new GPP is created, there’s an associated XML file created in SYSVOL with the relevant configuration data and if there is a password provided, it is AES-256 bit encrypted. Microsoft published the AES Key, which can be used to decrypt passwords store in: \\SYSVOL<DOMAIN>\Policies\
Credit: @cyb3rops
Source 1: https://twitter.com/cyb3rops/status/1036642978167758848
Source 2: https://adsecurity.org/?p=2288
[{"op":"From Base64","args":["A-Za-z0-9+/=",true]},{"op":"To Hex","args":["None"]},{"op":"AES Decrypt","args":[{"option":"Hex","string":"4e9906e8fcb66cc9faf49310620ffee8f496e806cc057990209b09a433b66c1b"},{"option":"Hex","string":""},"CBC","Hex","Raw",{"option":"Hex","string":""}]},{"op":"Decode text","args":["UTF16LE (1200)"]}]
CyberChef can use labels to identify parts of the recipe and then loop back to perform operations multiple times. In this examples, there are 29 rounds of Base64 encoding which are extracted and decoded.
Credit: @pmelson
Source File: hmCPDnHs.txt
Source 1: https://pastebin.com/hmCPDnHs
Source 2: https://twitter.com/pmelson/status/1078776229996752896
Also see more example of loops over Base64: https://twitter.com/QW5kcmV3/status/1079095274776289280 (Credit: @QW5kcmV3)
[{"op":"Label","args":["top"]},{"op":"Regular expression","args":["User defined","[a-zA-Z0-9+/=]{30,}",true,true,false,false,false,false,"List matches"]},{"op":"From Base64","args":["A-Za-z0-9+/=",true]},{"op":"Raw Inflate","args":[0,0,"Adaptive",false,false]},{"op":"Jump","args":["top",28]},{"op":"Generic Code Beautify","args":[]}]
Google uses its own timestamp, I call ei time, which it embeds in the URL.
Source: https://bitofhex.com/2018/05/29/cyberchef/
[{"op":"From Base64","args":["A-Za-z0-9-_=",true]},{"op":"To Hex","args":["None"]},{"op":"Take bytes","args":[0,8,false]},{"op":"Swap endianness","args":["Hex",4,true]},{"op":"From Base","args":[16]},{"op":"From UNIX Timestamp","args":["Seconds (s)"]}]
This is an eleven stage decoded COM scriplet that uses Base64, Gunzip, RegEx, and Disassemble x86 instructions.
Credit: @JohnLaTwC
Filename: 41a6e22ec6e60af43269f4eb1eb758c91cf746e0772cecd4a69bb5f6faac3578.txt
Source 2: https://twitter.com/JohnLaTwC/status/1062419803304976385
[{"op":"Regular expression","args":["","[A-Za-z0-9=/]{40,}",true,true,false,false,false,false,"List matches"]},{"op":"From Base64","args":["A-Za-z0-9+/=",true]},{"op":"Remove null bytes","args":[]},{"op":"Regular expression","args":["User defined","[A-Za-z0-9+/=]{40,}",true,true,false,false,false,false,"List matches"]},{"op":"From Base64","args":["A-Za-z0-9+/=",true]},{"op":"Gunzip","args":[]},{"op":"Regular expression","args":["User defined","[A-Za-z0-9+/=]{40,}",true,true,false,false,false,false,"List matches"]},{"op":"From Base64","args":["A-Za-z0-9+/=",true]},{"op":"To Hex","args":["Space"]},{"op":"Remove whitespace","args":[true,true,true,true,true,false]},{"op":"Disassemble x86","args":["32","Full x86 architecture",16,0,true,true]}]
This file has an embedded PE file (SHA 256: 26fac1d4ea12cdceac0d64ab9694d0582104b3c84d7940a4796c1df797d0fdc2, R5Sez8PH.exe, VT: 54/70). Using CyberChef, we can regex hexadecimal and the convert to a more easily viewable hexdump.
Source 1: https://pastebin.com/R5Sez8PH
Source 2: https://twitter.com/ScumBots/status/1081949877272276992
[{"op":"Regular expression","args":["User defined","[a-fA-F0-9]{200,}",true,true,false,false,false,false,"List matches"]},{"op":"From Hex","args":["Auto"]},{"op":"To Hexdump","args":[16,false,false]}]
A blob of base64 with some minor bytes to be substituted. Original decoding done by @pmelson in Python and converted to CyberChef.
Credit: @pmelson
Source 1: https://pastebin.com/RtjrweYF
Source 2: https://twitter.com/pmelson/status/1076893022758100998
[{"op":"Reverse","args":["Character"]},{"op":"Find / Replace","args":[{"option":"Regex","string":"%"},"A",true,false,true,false]},{"op":"Find / Replace","args":[{"option":"Regex","string":"×"},"T",true,false,false,false]},{"op":"Find / Replace","args":[{"option":"Simple string","string":"÷"},"V",true,false,false,false]},{"op":"From Base64","args":["A-Za-z0-9+/=",true]},{"op":"To Hexdump","args":[16,false,false]}]
Don't manually carve out your Squid cache objects. Simply upload the file to CyberChef. This recipe will search for the magic bytes 0x0D0A0D0A, extract everything after. It then gzip decompresses the object for download.
Source: 00000915 (output should be TrueCrypt_Setup_7.1a.exe with SHA256 e95eca399dfe95500c4de569efc4cc77b75e2b66a864d467df37733ec06a0ff2)
[{"op":"To Hex","args":["None"]},{"op":"Regular expression","args":["User defined","(?<=0D0A0D0A).*$",true,false,false,false,false,false,"List matches"]},{"op":"From Hex","args":["Auto"]},{"op":"Gunzip","args":[]}]
If you need to quickly triage where a photo was taken and you're lucky enought to have embedded GPS latitude and longitudes then use this recipe to quickly make a usable Google Maps URL to identify the location.
[{"op":"Extract EXIF","args":[]},{"op":"Regular expression","args":["User defined","((?<=GPSLatitude:).*$)|((?<=GPSLongitude: ).*$)",true,true,false,false,false,false,"List matches"]},{"op":"Find / Replace","args":[{"option":"Extended (\\n, \\t, \\x...)","string":"\\n"},",",true,false,true,false]},{"op":"Find / Replace","args":[{"option":"Simple string","string":" "},"https://maps.google.com/?q=",true,false,true,false]}]
CyberChef can handle massive numbers. Here we can use a simple recipe to change a 38-digit X509SerialNumber to its hexadecimal equivalent X.509 certificate serial number. Then we can regex the hexadecimal and insert a colon to transform it to the correct format.
Credit: @QW5kcmV3
Source: https://twitter.com/QW5kcmV3/status/949437437473968128
[{"op":"To Base","args":[16]},{"op":"Regular expression","args":["User defined","[a-f0-9]{2,2}",true,true,false,false,false,false,"List matches"]},{"op":"Find / Replace","args":[{"option":"Extended (\\n, \\t, \\x...)","string":"\\n"},":",true,false,true,false]}]
IP addresses in DNS PTR records are stored as least significant octet first. For example: 167.139.44.10.in-addr.arpa would relate to IP address of 10.44.139.167. Using CyberChef's registers we can allocate each octet to a memory register (or variable if it's easier to think of it that way). These can then be reversed to re-order the IP address. A find/replace tidies up the rest of the record. This could be reversed it you wanted to translate 'regular' IP addresses to search in DNS PTR records.
[{"op":"Fork","args":["\\n","\\n",false]},{"op":"Register","args":["(\\d{1,3}).(\\d{1,3}).(\\d{1,3}).(\\d{1,3})",true,false,false]},{"op":"Find / Replace","args":[{"option":"Regex","string":"$R0.$R1.$R2.$R3"},"$R3.$R2.$R1.$R0",true,false,true,false]},{"op":"Find / Replace","args":[{"option":"Regex","string":".in-addr.arpa"},"",true,false,true,false]}]
PoshC2 is a proxy aware C2 framework that utilises Powershell to aid penetration testers with red teaming, post-exploitation and lateral movement. The dropper is based on PowerShell and consists of a PowerShell script which is double Base64 encoded and compressed. Extracting the strings can be done with CyberChef as detailed below. Depending on the settings and customisation of the executable you may need to adjust your recipe.
Credit: @a_tweeter_user
Source: https://twitter.com/a_tweeter_user/status/1100751236687642624
Source: posh.zip (password: 'infected'. NB: this is different to the tweeted executable by @a_tweeter_user as I don't have a VT account)
[{"op":"Strings","args":["All",4,"Alphanumeric + punctuation (A)",false]},{"op":"Remove null bytes","args":[]},{"op":"Regular expression","args":["User defined","[a-zA-Z0-9+=]{200,}",true,true,false,false,false,false,"List matches"]},{"op":"From Base64","args":["A-Za-z0-9+/=",true]},{"op":"Remove null bytes","args":[]},{"op":"Regular expression","args":["User defined","[a-z0-9/\\\\+=]{100,}",true,true,false,false,false,false,"List matches"]},{"op":"From Base64","args":["A-Za-z0-9+/=",true]},{"op":"Raw Inflate","args":[0,0,"Adaptive",false,false]}]
CyberChef can do just about anything with data. Here are raw hex bytes from a $MFT entry. By selecting certain bytes, and using various functions of CyberChef I can parse any part of the data as needed. This recipe will extract and parse the $SI timestamps. Encase no more!
[{"op":"Take bytes","args":[160,64,false]},{"op":"Regular expression","args":["User defined",".{16}",true,true,true,false,false,false,"List matches with capture groups"]},{"op":"Fork","args":["\\n","\\n",false]},{"op":"Swap endianness","args":["Hex",10,true]},{"op":"Remove whitespace","args":[true,true,true,true,true,false]},{"op":"Windows Filetime to UNIX Timestamp","args":["Nanoseconds (ns)","Hex"]},{"op":"From UNIX Timestamp","args":["Nanoseconds (ns)"]},{"op":"Merge","args":[]},{"op":"Register","args":["(.*)\\n(.*)\\n(.*)\\n(.*)",true,false,false]},{"op":"Find / Replace","args":[{"option":"Regex","string":"$R0"},"$SI Creation Time: $R0",true,false,true,false]},{"op":"Find / Replace","args":[{"option":"Regex","string":"$R1"},"$SI Modified Time: $R1",true,false,true,false]},{"op":"Find / Replace","args":[{"option":"Regex","string":"$R2"},"$SI MFT Change Time: $R2",true,false,true,false]},{"op":"Find / Replace","args":[{"option":"Regex","string":"$R3"},"$SI Access Time: $R3",false,false,true,false]}]
Webshells come in all shapes and sizes. For PHP webshells the combination of gzinflate and base64 can be used to obfuscate the eval data. In this example, there are 21 rounds of compression and base64 that we can quickly parse out using labels and loops.
[{"op":"Label","args":["start"]},{"op":"Regular expression","args":["User defined","[a-zA-Z0-9=/+]{10,}",true,true,false,false,false,false,"List matches"]},{"op":"From Base64","args":["A-Za-z0-9+/=",true]},{"op":"Raw Inflate","args":[0,0,"Block",false,false]},{"op":"Jump","args":["start",21]}]
Often seen in @pmelson's Pastbin bot @scumbots, this peels away multiple layers of an encoded Powershell script to display the shellcode. From here you could extract PUSH statements to try and identify the IP address & port, but you'll get too many false positives. So you're better off using a tool like scdbg (see: http://sandsprite.com/blogs/index.php?uid=7&pid=152)
Source: https://twitter.com/ScumBots/status/1121854255898472453
Source: https://pastebin.com/9DnD6t6W
[{"op":"Regular expression","args":["User defined","[a-zA-Z0-9=/+]{30,}",true,true,false,false,false,false,"List matches"]},{"op":"From Base64","args":["A-Za-z0-9+/=",true]},{"op":"Remove null bytes","args":[]},{"op":"Regular expression","args":["User defined","[a-zA-Z0-9=/+]{30,}",true,true,false,false,false,false,"List matches"]},{"op":"From Base64","args":["A-Za-z0-9+/=",true]},{"op":"Gunzip","args":[]},{"op":"Regular expression","args":["User defined","[a-zA-Z0-9=/+]{30,}",true,true,false,false,false,false,"List matches"]},{"op":"From Base64","args":["A-Za-z0-9+/=",true]},{"op":"To Hex","args":["None"]},{"op":"Disassemble x86","args":["32","Full x86 architecture",16,0,true,true]}]
Subsections and Merges are powerful tools in CyberChef that allow the application of ingredients to a selection of data rather than the whole input file. This section can then be merged together to continue on the whole input. In an awesome piece of work @GlassSec has created a Windows Recycle Bin parser using CyberChef indicating the possibilities of these functions is endless.
Source: https://gist.github.com/glassdfir/f30957b314ec39a8aa319420a29ffc76
Credit: https://twitter.com/GlassSec
[{"op":"Conditional Jump","args":["^(\\x01|\\x02)",true,"Error",10]},{"op":"Find / Replace","args":[{"option":"Regex","string":"^(\\x02.{23})(....)"},"$1",false,false,false,false]},{"op":"Subsection","args":["^.{24}(.*)",true,true,false]},{"op":"Decode text","args":["UTF16LE (1200)"]},{"op":"Find / Replace","args":[{"option":"Regex","string":"^(.*)."},"\\nDeleted File Path: $1",false,false,false,false]},{"op":"Merge","args":[]},{"op":"Subsection","args":["^.{16}(.{8})",false,true,false]},{"op":"Swap endianness","args":["Raw",8,true]},{"op":"To Hex","args":["None"]},{"op":"Windows Filetime to UNIX Timestamp","args":["Seconds (s)","Hex"]},{"op":"From UNIX Timestamp","args":["Seconds (s)"]},{"op":"Find / Replace","args":[{"option":"Regex","string":"^(.* UTC)"},"\\nFile Deletion Time: $1",true,false,true,false]},{"op":"Merge","args":[]},{"op":"Subsection","args":["^.{8}(.{8})",true,true,false]},{"op":"To Hex","args":["None"]},{"op":"Swap endianness","args":["Hex",8,true]},{"op":"From Base","args":[16]},{"op":"Find / Replace","args":[{"option":"Regex","string":"^(.*)"},"\\nDeleted File Size: $1 bytes",true,false,true,true]},{"op":"Merge","args":[]},{"op":"Find / Replace","args":[{"option":"Regex","string":"^.{8}"},"******** WINDOWS RECYCLE BIN METADATA ********",true,false,false,false]},{"op":"Jump","args":["Do Nothing",10]},{"op":"Label","args":["Error"]},{"op":"Find / Replace","args":[{"option":"Regex","string":"^.*$"},"This doesn't look like a Recycle Bin file to me ",true,false,true,false]},{"op":"Label","args":["Do Nothing"]}]
Less of a recipe and more of a technique. Using the 'highlight' function of the regular expression ingredient can clearly bring out where base64 data has been broken up with non-traditional base64 character set. Here the sequence '@<!' is used to obfuscate and disrupt automated encoding conversion. Looking further down the script, the sequence is substituted with 'A', which can then be inserted with a Find/Replace prior to the extraction. This continues for multiple rounds until a domain of interest is revealed (along with an executable prior).
Source: https://pastebin.com/TmJsB0Nv & https://twitter.com/pmelson/status/1167065236907659264
[{"op":"Find / Replace","args":[{"option":"Simple string","string":"@<!"},"A",true,false,true,false]},{"op":"Regular expression","args":["User defined","[a-zA-Z0-9+/=]{20,}",true,true,false,false,false,false,"List matches"]},{"op":"From Base64","args":["A-Za-z0-9+/=",true]},{"op":"Regular expression","args":["User defined","[a-zA-Z0-9+/=]{50,}",true,true,false,false,false,false,"List matches"]},{"op":"From Base64","args":["A-Za-z0-9+/=",true]},{"op":"Find / Replace","args":[{"option":"Simple string","string":"@<!"},"A",true,false,true,false]},{"op":"Regular expression","args":["User defined","[a-zA-Z0-9+/=]{50,}",true,true,false,false,false,false,"List matches"]},{"op":"From Base64","args":["A-Za-z0-9+/=",true]}]
Although not the most convenient way, CyberChef does provide the ability to run a yara rule over the output of a recipe. You could combine this by using the multiple inputs function to scan a larger number of files.
Source: https://twitter.com/ScumBots/status/1168528510681538560 & https://pastebin.com/r40SXe7V
[{"op":"Regular expression","args":["User defined","\\(.*\\);",true,false,false,false,false,false,"List matches"]},{"op":"Find / Replace","args":[{"option":"Regex","string":",|\\(|\\);"}," ",true,false,true,false]},{"op":"From Charcode","args":["Space",10]},{"op":"YARA Rules","args":["rule SuspiciousPowerShell {\n meta:\n description = \"Testing Yara on Cyberchef for Powershell\"\n strings:\n $a1 = \"[System.Reflection.Assembly]\" ascii\n $a2 = \"IEX\" ascii nocase\n $a3 = \"powershell.exe -w hidden -ep bypass -enc\" ascii\n condition:\n 2 of them\n}",true,true,true,true]}]
Happy to add (and learn) more. Pull request or tweet to @mattnotmax!
Please include original source of text and recipe developer (if not yourself). For consistency in pasting into CyberChef I have found the best results are to export the function as compact JSON.