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MALPEDIA_Win_Postnaptea_Auto

autogenerated rule brought to you by yara-signator

MalwarePostnapteaMalpedia 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: Postnaptea.

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

Summary generated from the rule's metadata and condition.

Rule source

win-postnaptea-auto.yarCreative Commons Attribution-ShareAlike 4.0
rule MALPEDIA_Win_Postnaptea_Auto : FILE
{
	meta:
		description = "autogenerated rule brought to you by yara-signator"
		author = "Felix Bilstein - yara-signator at cocacoding dot com"
		id = "2c2d9707-07ad-5243-85f1-210116caa2a9"
		date = "2026-05-04"
		modified = "2026-05-18"
		reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.postnaptea"
		source_url = "https://github.com/malpedia/signator-rules//blob/c901f97b7df03e41917da74c2a84b04c227316c2/rules/win.postnaptea_auto.yar#L1-L134"
		license_url = "N/A"
		logic_hash = "5c2b930508b20d9de8e8f9b631eefff2fbcc2a62f0d5a8b36c9dc821d8d4ca8a"
		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 = { e8???????? eb05 e8???????? 488d5550 488d4df0 e8???????? c1e81f }
		$sequence_1 = { c745c40cf511f5 c745c815f546f5 c745cc0af50df5 c745d004f508f5 c745d40ef51ef5 c745d81ef506f5 c745dc06f500f5 }
		$sequence_2 = { c7459410f511f5 c7459806f505f5 c7459c11f50df5 c745a015f516f5 c745a402f552f5 c745a877f574f5 33c0 }
		$sequence_3 = { c7459059f540f5 c745945bf50000 660f1f840000000000 4863c2 488d4c2450 488d0c41 0fb7c2 }
		$sequence_4 = { c785e005000010f552f5 c785e405000015f51df5 c785e805000019f513f5 c785ec05000057f51ef5 c785f005000018f513f5 c785f405000017f519f5 c785f805000019f55ef5 }
		$sequence_5 = { 0f871b010000 488bce e8???????? 90 4983fd08 0f8208ffffff 4a8d146d02000000 }
		$sequence_6 = { c7851c0b00000ef50bf5 c785200b000017f51ff5 c785240b00005df548f5 c785280b000020f504f5 c7852c0b00004bf539f5 c785300b00001ef50bf5 c785340b000055f50000 }
		$sequence_7 = { e8???????? 488905???????? 498b4f18 ffd0 48898540010000 488b8dd8000000 488b01 }
		$sequence_8 = { e8???????? 8bd6 488d4bd8 e8???????? 33d2 41b808020000 488d8d90050000 }
		$sequence_9 = { e9???????? 4883fa10 722d 48ffc2 488b4d80 488bc1 4881fa00100000 }

	condition:
		7 of them and filesize < 2457600
}

Strings (10 patterns)

IdentifierTypeValueModifiers
$sequence_0hex{ e8???????? eb05 e8???????? 488d5550 488d4df0 e8???????? c1e81f }
$sequence_1hex{ c745c40cf511f5 c745c815f546f5 c745cc0af50df5 c745d004f508f5 c745d40ef51ef5 c745d81ef506f5 c745dc06f500f5 }
$sequence_2hex{ c7459410f511f5 c7459806f505f5 c7459c11f50df5 c745a015f516f5 c745a402f552f5 c745a877f574f5 33c0 }
$sequence_3hex{ c7459059f540f5 c745945bf50000 660f1f840000000000 4863c2 488d4c2450 488d0c41 0fb7c2 }
$sequence_4hex{ c785e005000010f552f5 c785e405000015f51df5 c785e805000019f513f5 c785ec05000057f51ef5 c785f005000018f513f5 c785f405000017f519f5 c785f805000019f55ef5 }
$sequence_5hex{ 0f871b010000 488bce e8???????? 90 4983fd08 0f8208ffffff 4a8d146d02000000 }
$sequence_6hex{ c7851c0b00000ef50bf5 c785200b000017f51ff5 c785240b00005df548f5 c785280b000020f504f5 c7852c0b00004bf539f5 c785300b00001ef50bf5 c785340b000055f50000 }
$sequence_7hex{ e8???????? 488905???????? 498b4f18 ffd0 48898540010000 488b8dd8000000 488b01 }
$sequence_8hex{ e8???????? 8bd6 488d4bd8 e8???????? 33d2 41b808020000 488d8d90050000 }
$sequence_9hex{ e9???????? 4883fa10 722d 48ffc2 488b4d80 488bc1 4881fa00100000 }

Condition

7 of them and filesize < 2457600

In plain words (Heuristic)

  • The file must be smaller than 2457600 (a cheap guard that skips large files).
  • At least 7 patterns in the rule must match.

Test this rule in your browser

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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: 2c2d9707-07ad-5243-85f1-210116caa2a9

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