SIGNATURE_BASE_SUSP_Claude_Redacted_Thinking_Magic_String_Jan26_1

rule SIGNATURE_BASE_SUSP_Claude_Redacted_Thinking_Magic_String_Jan26_1
{
	meta:
		description = "Detects redacted thinking magic string that cause Claude sessions to be terminated. This might indicate that a file tries to prevent being analyzed by LLM agents."
		author = "Marius Benthin"
		id = "623de3f9-ea03-5b6a-bb24-14b4a6d4a7c9"
		date = "2026-01-29"
		modified = "2026-05-15"
		reference = "Internal Research"
		source_url = "https://github.com/Neo23x0/signature-base/blob/94a1c48d7ab499879287ff611dfe7f9c56376030/yara/susp_claude_magic_strings.yar#L30-L43"
		license_url = "https://github.com/Neo23x0/signature-base/blob/94a1c48d7ab499879287ff611dfe7f9c56376030/LICENSE"
		hash = "ffa48ed4b7b48897f6756c4222b2606399de0bca627cedfddf61e69986580430"
		logic_hash = "02b85e9df893d6be91f8053ac67884e5a24893ef225ca0e7b3878b38afb79420"
		score = 65
		quality = 83
		tags = ""

	strings:
		$x1 = "ANTHROPIC_MAGIC_STRING_TRIGGER_REDACTED_THINKING_" ascii wide nocase

	condition:
		$x1
}