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SIGNATURE_BASE_SUSP_PY_Shell_Spawn_Jun23_1

Detects suspicious one-liner to spawn a shell using Python

Suspicious / huntingSignature Base (Florian Roth / Nextron)Detection Rule License 1.1Compiles with YARA-X
Author
Florian Roth
Date
2023-06-15
Modified
2023-12-05
Score / Quality
70 / 85

What this rule detects

Detects suspicious one-liner to spawn a shell using Python

It defines 1 patterns (1 text, 0 hex, 0 regex).

Summary generated from the rule's metadata and condition.

Rule source

Download .yar
susp-py-shell-spawn-jun23-1.yarDetection Rule License 1.1
rule SIGNATURE_BASE_SUSP_PY_Shell_Spawn_Jun23_1 : SCRIPT
{
	meta:
		description = "Detects suspicious one-liner to spawn a shell using Python"
		author = "Florian Roth"
		id = "15fd2c9a-c425-5d4d-9209-fd3826074d6c"
		date = "2023-06-15"
		modified = "2023-12-05"
		reference = "https://www.mandiant.com/resources/blog/barracuda-esg-exploited-globally"
		source_url = "https://github.com/Neo23x0/signature-base/blob/94a1c48d7ab499879287ff611dfe7f9c56376030/yara/apt_barracuda_esg_unc4841_jun23.yar#L119-L131"
		license_url = "https://github.com/Neo23x0/signature-base/blob/94a1c48d7ab499879287ff611dfe7f9c56376030/LICENSE"
		logic_hash = "63e94447930d5a00399de753076facbfb2bf18dd8c815f01aaefd14678aea034"
		score = 70
		quality = 85
		tags = "SCRIPT"

	strings:
		$x1 = "python -c import pty;pty.spawn(\"/bin/" ascii

	condition:
		1 of them
}

Strings (1 patterns)

IdentifierTypeValueModifiers
$x1text"python -c import pty;pty.spawn(\"/bin/"ascii

Condition

1 of them

In plain words (Heuristic)

  • At least 1 patterns in the rule must match.

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References

Licence & attribution

Author: Florian Roth

Source repository: Signature Base (Florian Roth / Nextron) @ 94a1c48d7a

Licence: Detection Rule License 1.1 (repository licence)

Original rule

Mirrored via YARA Forge 20260927, which prefixes rule names with the source and adds normalised meta fields.

Rule id: 15fd2c9a-c425-5d4d-9209-fd3826074d6c

Tags:SCRIPT

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