YARA · Signature Base (Florian Roth / Nextron)
SIGNATURE_BASE_SUSP_Screenconnect_User_Poc_Com_Unused_Feb24
Detects suspicious ScreenConnect user with poc.com email address, which is a sign of exploitation of the ConnectWise ScreenConnect (versions prior to 23.9.8) vulnerability with the POC released by WatchTower and the account wasn't actually used yet to login
- Author
- Florian Roth
- Date
- 2024-02-23
- Modified
- 2024-04-24
- Score / Quality
- 65 / 85
What this rule detects
Detects suspicious ScreenConnect user with poc.com email address, which is a sign of exploitation of the ConnectWise ScreenConnect (versions prior to 23.9.8) vulnerability with the POC released by WatchTower and the account wasn't actually used yet to login
It defines 4 patterns (4 text, 0 hex, 0 regex).
Summary generated from the rule's metadata and condition.
Rule source
rule SIGNATURE_BASE_SUSP_Screenconnect_User_Poc_Com_Unused_Feb24 : FILE
{
meta:
= "Detects suspicious ScreenConnect user with poc.com email address, which is a sign of exploitation of the ConnectWise ScreenConnect (versions prior to 23.9.8) vulnerability with the POC released by WatchTower and the account wasn't actually used yet to login"
= "Florian Roth"
= "c57e6c6a-298f-5ff3-b76a-03127ff88699"
= "2024-02-23"
= "2024-04-24"
= "https://github.com/watchtowrlabs/connectwise-screenconnect_auth-bypass-add-user-poc/blob/45e5b2f699a4d8f2d59ec3fc79a2e3c99db71882/watchtowr-vs-ConnectWise_2024-02-21.py#L53"
= "https://github.com/Neo23x0/signature-base/blob/94a1c48d7ab499879287ff611dfe7f9c56376030/yara/expl_connectwise_screenconnect_vuln_feb24.yar#L20-L38"
= "https://github.com/Neo23x0/signature-base/blob/94a1c48d7ab499879287ff611dfe7f9c56376030/LICENSE"
= "2433ad11ca1d9f970eb3c536a13f07e808c2a0b8b0dd625dffbe4947268ab8f5"
= 65
= 85
= "FILE"
strings:
$a1 = "<Users xmlns:xsi="
$a2 = "<CreationDate>"
$s1 = "@poc.com</Email>"
$s2 = "<LastLoginDate>0001"
condition:
filesize < 200KB and all of ( $a* ) and all of ( $s* )
}
Strings (4 patterns)
| Identifier | Type | Value | Modifiers |
|---|---|---|---|
| $a1 | text | "<Users xmlns:xsi=" | |
| $a2 | text | "<CreationDate>" | |
| $s1 | text | "@poc.com</Email>" | |
| $s2 | text | "<LastLoginDate>0001" |
Condition
filesize < 200KB and all of ( $a* ) and all of ( $s* )In plain words (Heuristic)
- The file must be smaller than 200KB (a cheap guard that skips large files).
- All patterns in ( $a* ) must match.
- All patterns in ( $s* ) must match.
Test this rule in your browser
Drop a file to scan it with this rule using YARA-X compiled to WebAssembly. Nothing is uploaded.
Licence & attribution
Author: Florian Roth
Source repository: Signature Base (Florian Roth / Nextron) @ 94a1c48d7a
Licence: Detection Rule License 1.1 (repository licence)
Mirrored via YARA Forge 20260927, which prefixes rule names with the source and adds normalised meta fields.
Rule id: c57e6c6a-298f-5ff3-b76a-03127ff88699
Tags:FILE
Related rules
- Suspicious / huntingSignature Base (Florian Roth / Nextron)· Florian Roth· 2024-02-23
- Suspicious / huntingSignature Base (Florian Roth / Nextron)· Florian Roth· 2024-02-23
- Suspicious / huntingSignature Base (Florian Roth / Nextron)· Florian Roth· 2024-10-25
- Suspicious / huntingSignature Base (Florian Roth / Nextron)· Florian Roth· 2024-02-23
- Suspicious / huntingSignature Base (Florian Roth / Nextron)· Florian Roth· 2023-08-04
- Suspicious / huntingSignature Base (Florian Roth / Nextron)· Florian Roth· 2024-02-23
- Suspicious / huntingSignature Base (Florian Roth / Nextron)· Florian Roth· 2025-08-07
- Suspicious / huntingSignature Base (Florian Roth / Nextron)· Florian Roth· 2025-02-14