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MALPEDIA_Win_Rc2Fm_Auto

autogenerated rule brought to you by yara-signator

MalwareRc2FmMalpedia signator rulesCreative Commons Attribution-ShareAlike 4.0Compiles with YARA-X
Author
Felix Bilstein - yara-signator at cocacoding dot com
Date
2026-05-04
Modified
2026-05-18
Score / Quality
75 / 75

What this rule detects

autogenerated rule brought to you by yara-signator

Associated malware family: Rc2Fm.

It defines 10 patterns (0 text, 10 hex, 0 regex).

Summary generated from the rule's metadata and condition.

Rule source

win-rc2fm-auto.yarCreative Commons Attribution-ShareAlike 4.0
rule MALPEDIA_Win_Rc2Fm_Auto : FILE
{
	meta:
		description = "autogenerated rule brought to you by yara-signator"
		author = "Felix Bilstein - yara-signator at cocacoding dot com"
		id = "a08a9a06-9998-5e1d-a729-c63a91aa11fb"
		date = "2026-05-04"
		modified = "2026-05-18"
		reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.rc2fm"
		source_url = "https://github.com/malpedia/signator-rules//blob/c901f97b7df03e41917da74c2a84b04c227316c2/rules/win.rc2fm_auto.yar#L1-L128"
		license_url = "N/A"
		logic_hash = "70864d4a72a67efe883f8d2dfa51c4b27e988571cf0f95ac8e7ae0d473a661a2"
		score = 75
		quality = 75
		tags = "FILE"
		version = "1"
		tool = "yara-signator v0.6.0"
		signator_config = "callsandjumps;datarefs;binvalue"
		malpedia_rule_date = "20260422"
		malpedia_hash = "a182e35da64e6d71cb55f125c4d4225196523f14"
		malpedia_version = "20260504"
		malpedia_license = "CC BY-SA 4.0"
		malpedia_sharing = "TLP:WHITE"

	strings:
		$sequence_0 = { 488d4c2448 c605????????01 e8???????? 84c0 7531 }
		$sequence_1 = { 488d4507 4403c9 488d156d6c0100 4c8bc3 33c9 4889442420 e8???????? }
		$sequence_2 = { 0fb64c246a 884c245e 0fb64c246e 88442461 0fb6442474 884c245f 0fb64c2470 }
		$sequence_3 = { 4c8ba42460050000 4885c0 7412 488b0d???????? 4c8bc0 33d2 ff15???????? }
		$sequence_4 = { 0fb7d5 4c8908 8b07 6642893408 830702 8b07 46892408 }
		$sequence_5 = { 48f7d9 4d8d82a0b00200 4d8d8aa1b00200 4c03c1 4c03c9 b9000a0000 6666660f1f840000000000 }
		$sequence_6 = { 4055 53 4154 4155 488dac24a8fdffff }
		$sequence_7 = { 448bf2 418be8 4c8bf9 8d5707 3bc7 }
		$sequence_8 = { 4885c0 7431 4533c9 4533c0 33c9 418d5101 48896bf8 }
		$sequence_9 = { 448d4804 0fb60a 80f961 7203 80c1e0 c1c80b 0fb6c9 }

	condition:
		7 of them and filesize < 410624
}

Strings (10 patterns)

IdentifierTypeValueModifiers
$sequence_0hex{ 488d4c2448 c605????????01 e8???????? 84c0 7531 }
$sequence_1hex{ 488d4507 4403c9 488d156d6c0100 4c8bc3 33c9 4889442420 e8???????? }
$sequence_2hex{ 0fb64c246a 884c245e 0fb64c246e 88442461 0fb6442474 884c245f 0fb64c2470 }
$sequence_3hex{ 4c8ba42460050000 4885c0 7412 488b0d???????? 4c8bc0 33d2 ff15???????? }
$sequence_4hex{ 0fb7d5 4c8908 8b07 6642893408 830702 8b07 46892408 }
$sequence_5hex{ 48f7d9 4d8d82a0b00200 4d8d8aa1b00200 4c03c1 4c03c9 b9000a0000 6666660f1f840000000000 }
$sequence_6hex{ 4055 53 4154 4155 488dac24a8fdffff }
$sequence_7hex{ 448bf2 418be8 4c8bf9 8d5707 3bc7 }
$sequence_8hex{ 4885c0 7431 4533c9 4533c0 33c9 418d5101 48896bf8 }
$sequence_9hex{ 448d4804 0fb60a 80f961 7203 80c1e0 c1c80b 0fb6c9 }

Condition

7 of them and filesize < 410624

In plain words (Heuristic)

  • The file must be smaller than 410624 (a cheap guard that skips large files).
  • At least 7 patterns in the rule must match.

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References

Licence & attribution

Author: Felix Bilstein - yara-signator at cocacoding dot com

Source repository: Malpedia signator rules @ c901f97b7d

Licence: Creative Commons Attribution-ShareAlike 4.0 (repository licence)

Original rule

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

Rule id: a08a9a06-9998-5e1d-a729-c63a91aa11fb

Metadata

version1
toolyara-signator v0.6.0
signator_configcallsandjumps;datarefs;binvalue
malpedia_rule_date20260422
malpedia_hasha182e35da64e6d71cb55f125c4d4225196523f14
malpedia_version20260504
malpedia_licenseCC BY-SA 4.0
malpedia_sharingTLP:WHITE

Tags:FILE