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Custom curl query?

Does anyone know of or have a custom live discover query that can identify any processes, programs running cURL? I am seeing something to help identify the vulnerability located in CVE-2023-38545.

Description

The version of curl installed on the remote host is affected by a heap based buffer overflow in the SOCKS5 proxy handshake. When curl is asked to pass along the hostname to the SOCKS5 proxy to allow that to resolve the address instead of it getting done by curl itself, the maximum length that hostname can be is 255 bytes. If the hostname is detected to be longer than 255 bytes, curl switches to local name resolving and instead passes on the resolved address only to the proxy. Due to a bug, the local variable that means 'let the host resolve the name' could get the wrong value during a slow SOCKS5 handshake, and contrary to the intention, copy the too long hostname to the target buffer instead of copying just the resolved address there.

Andrew Bishop
  • in reply to Andrew Bishop
    Works OK for me, this is a Live Query rather than datalake. /resized-image/__size/1280x960/__key/commentfiles/fb5d84b10a5745448a7a45dafc1faa43-9120aad2-3ebd-4008-8c5c-2ced9f4a4740/pastedimage1700692975396v1.png
  • in reply to Sophos User930
    Hi sorry for the delayed response. I had the search set to run all of this week and so far everything has returned a "Failure to execute."
  • in reply to Andrew Bishop
    Hello,  I'm curious if it was helpful and if it returned what you might have expected and if a manual double check confirmed it was expected?  I'm sure it could be refined but OK as a starting point?  The time it goes back in the journals is is only 15 minutes by default, so it would have only returned data for processes that loaded libcurl that wasn't 8.4 in the last 15 minutes.  The "time" > epoch could be used as needed. Thanks
  • in reply to Andrew Bishop
    What about: with file_list as ( select spj.cmd_line, sfj.path, sfj.file from sophos_file_journal as sfj join sophos_process_journal as spj on spj.sophos_pid = sfj.sophos_pid where sfj.subject = "FileBinaryReads" and sfj.event_type = 9 and sfj.file like '%libcurl%' ) select * from file_list join file as osqfile on osqfile.path = file_list.path where osqfile.file_version not like '8.4%' You can get hashes and things, you could join on file_id as well but that could restrict to the same drive. Maybe see what that returns. It is using the standard file table of osquery to get the file version (and all other fields) for the path
  • in reply to Sophos User930
    I am looking for something to help identify this vulnerability. Description The version of curl installed on the remote host is affected by a heap based buffer overflow in the SOCKS5 proxy handshake. When curl is asked to pass along the hostname to the SOCKS5 proxy to allow that to resolve the address instead of it getting done by curl itself, the maximum length that hostname can be is 255 bytes. If the hostname is detected to be longer than 255 bytes, curl switches to local name resolving and instead passes on the resolved address only to the proxy. Due to a bug, the local variable that means 'let the host resolve the name' could get the wrong value during a slow SOCKS5 handshake, and contrary to the intention, copy the too long hostname to the target buffer instead of copying just the resolved address there. CVE-2023-38545 Solution Upgrade curl to version 8.4.0 or later
  • in reply to Sophos User930
    As a very basic start: select spj.cmd_line, sfj.path from sophos_file_journal as sfj join sophos_process_journal as spj on spj.sophos_pid = sfj.sophos_pid where sfj.subject = "FileBinaryReads" and sfj.event_type = 9 and sfj.file like '%libcurl%' limit 20; We can see for example that the NP++ updater uses libcurl.  I did just create a test exe that uses libcurl, just to generate some data /resized-image/__size/1280x960/__key/commentfiles/fb5d84b10a5745448a7a45dafc1faa43-9120aad2-3ebd-4008-8c5c-2ced9f4a4740/pastedimage1700153168289v1.png
  • Are you interested in processes that load libcurl.dll/libcurl-x64.dll for example? E.g. You might build an exe that uses the libcurl library and your interested in those or are you interested in processes that shell out to curl.exe? 
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