Skip to content
yararules.org
Menu

YARA · Signature Base (Florian Roth / Nextron)

SIGNATURE_BASE_SUSP_Themebleed_Theme_Sep23

Detects domain or IP placement in Windows theme files

Suspicious / huntingSignature Base (Florian Roth / Nextron)Detection Rule License 1.1Compiles with YARA-X
Author
@m_haggis, @nas_bench
Date
2023-09-13
Modified
2023-12-05
Score / Quality
75 / 85

What this rule detects

Detects domain or IP placement in Windows theme files

It defines 3 patterns (2 text, 0 hex, 1 regex).

Summary generated from the rule's metadata and condition.

Rule source

Download .yar
susp-themebleed-theme-sep23.yarDetection Rule License 1.1
rule SIGNATURE_BASE_SUSP_Themebleed_Theme_Sep23 : FILE
{
	meta:
		description = "Detects domain or IP placement in Windows theme files"
		author = "@m_haggis, @nas_bench"
		id = "76d0042b-655d-5d03-bcc4-150ebc92eb43"
		date = "2023-09-13"
		modified = "2023-12-05"
		reference = "https://github.com/gabe-k/themebleed"
		source_url = "https://github.com/Neo23x0/signature-base/blob/94a1c48d7ab499879287ff611dfe7f9c56376030/yara/exploit_cve_2023_38146.yar#L1-L17"
		license_url = "https://github.com/Neo23x0/signature-base/blob/94a1c48d7ab499879287ff611dfe7f9c56376030/LICENSE"
		logic_hash = "577003741f07aeffafd2b0b22913de44ea4f5ed264f4104ee013104355f65311"
		score = 75
		quality = 85
		tags = "FILE"

	strings:
		$s1 = /Path=\\\\[0-9a-zA-Z\.-]{1,20}\\/
		$s2 = "[VisualStyles]"
		$s3 = "[Theme]"

	condition:
		filesize < 1MB and all of them
}

Strings (3 patterns)

IdentifierTypeValueModifiers
$s1regex/Path=\\\\[0-9a-zA-Z\.-]{1,20}\\/
$s2text"[VisualStyles]"
$s3text"[Theme]"

Condition

filesize < 1MB and all of them

In plain words (Heuristic)

  • The file must be smaller than 1MB (a cheap guard that skips large files).
  • All patterns in the rule 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.

Drop a file here or click to chooseScanned locally with YARA-X. Files up to 200 MB.

Open in editor

References

Licence & attribution

Author: @m_haggis, @nas_bench

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: 76d0042b-655d-5d03-bcc4-150ebc92eb43

Tags:FILE