Comments (3)
Hi @nbareil,
So unfortunately not all the Sigma rules are written that well. The reason that Chainsaw won't parse this one into a Tau compatible format is because selection_conf
does not specify a field to search upon for the string Sysmon config state changed
.
If its intended behaviour for this rule to run upon all key value pairs within an event log entry then we can add support for that (it will be slow though) but I don't think that is what this rule is meant to do.
Let me know what you think.
from chainsaw.
Thanks for your fast answer Alex!
I know almost nothing about Sigma but from its specifications, this construction looks to be allowed by the language:
2.9.4. Lists
Lists can contain:
- strings that are applied to the full log message and are linked with a logical 'OR'.
- maps (see below). All map items of a list are logically linked with 'OR'.
Example for list of strings: Matches on 'EvilService' or 'svchost.exe -n evil'
detection: keywords: - EVILSERVICE - svchost.exe -n evil
Now, as said, there are only 93 out of 2400 rules in SigmaHQ that do not parse, I don't think it is a big deal and I do not have any opinion if you should implement it or not, if you feel this change is more problematic than helpful, feel free to close this issue with WONTFIX 🤗
Kind regards
from chainsaw.
Exaclty, its allowed in their spec but its allows for inefficient rules to be written. It is basically saying look for those values anywhere in the entry (full log message). When we are processing structured data (like event logs, json, xml, etc) the concept of a full log message
does not really make sense, the author must has fields in mind they would like to match. I would argue that its lazy rule writing to not specify the fields that would would like to search on.
Thanks for your understanding, I will mark as won't fix unless a burning desire arises to need this feature.
Oh and the other ones that can't convert are usually using thinks like inefficient regex which Rust does not support. I will have another look again when I get time to see if I can easily get any of the final 93 in.
from chainsaw.
Related Issues (20)
- Incorrect hunt examples displayed HOT 1
- Definition of "logsource" values like product or category. HOT 12
- Add timestamp format to help output HOT 2
- Deserialization error does't not show responsible file HOT 2
- Invalid Tau Key Pair error HOT 2
- Hunt with WEC/WEF HOT 2
- Check for potential I/0 error before processing HOT 1
- Erroneous Sigma Results using Hunt option HOT 7
- chainsaw project name collides with another rust project HOT 2
- Tau EventID Filter error HOT 6
- v2.4+ seems to be unable to recognize Sigma alerts HOT 1
- Sophos Antivirus Rule Not Parsing Data Events With Same Key Name HOT 5
- Print warning when loading Sigma rules with keyless search identifiers HOT 6
- Missing Sigma Base64 Encoding? HOT 3
- -o flag not recognized HOT 2
- No executable HOT 1
- Looking for clarity for mft yaml 'filter' issue HOT 3
- [Feature Request] Support for "contains", "|" and "all" in both chainsaw and sigma rules HOT 4
- Search feature doesn't parse backslashes HOT 2
Recommend Projects
-
React
A declarative, efficient, and flexible JavaScript library for building user interfaces.
-
Vue.js
🖖 Vue.js is a progressive, incrementally-adoptable JavaScript framework for building UI on the web.
-
Typescript
TypeScript is a superset of JavaScript that compiles to clean JavaScript output.
-
TensorFlow
An Open Source Machine Learning Framework for Everyone
-
Django
The Web framework for perfectionists with deadlines.
-
Laravel
A PHP framework for web artisans
-
D3
Bring data to life with SVG, Canvas and HTML. 📊📈🎉
-
Recommend Topics
-
javascript
JavaScript (JS) is a lightweight interpreted programming language with first-class functions.
-
web
Some thing interesting about web. New door for the world.
-
server
A server is a program made to process requests and deliver data to clients.
-
Machine learning
Machine learning is a way of modeling and interpreting data that allows a piece of software to respond intelligently.
-
Visualization
Some thing interesting about visualization, use data art
-
Game
Some thing interesting about game, make everyone happy.
Recommend Org
-
Facebook
We are working to build community through open source technology. NB: members must have two-factor auth.
-
Microsoft
Open source projects and samples from Microsoft.
-
Google
Google ❤️ Open Source for everyone.
-
Alibaba
Alibaba Open Source for everyone
-
D3
Data-Driven Documents codes.
-
Tencent
China tencent open source team.
from chainsaw.