Malicious PDF — malware analysis report

Static analysis result for SHA-256 5c1e088e6cc5bd78…

MALICIOUS

PDF

81.2 KB Created: 2021-09-08 19:54:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: dc48894a7f161350a4fc47b3c9cdb03f SHA-1: 36be756bd0739ec23f032e378171b5af27642c7e SHA-256: 5c1e088e6cc5bd78a4222da95a0eebc1a8201c04816afc2414739a3bebe03067
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains embedded JavaScript and a high number of external URIs, many pointing to PDF files on disposable domains, indicating a link farm designed to host malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution via the linked PDFs. The embedded JavaScript is likely used to obfuscate the links or perform further malicious actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://berbagiangka.com/contents/files/7240959946.pdf In PDF document text
    • https://luckysurface.itweald.com/uploads/files/61307498ecb6d.pdfIn PDF document text
    • http://ranfeng.com/userfiles/file/2021-9///202197223532913.pdfIn PDF document text
    • http://e2ingenieros.com/ckfinder/userfiles/files/62275265601.pdfIn PDF document text
    • http://28777886.com/Lpf/UPFILE/userfiles/files/xotukoramar.pdfIn PDF document text
    • http://zezoalza.com/ckupload/files/bewake.pdfIn PDF document text
    • http://somersetcountybar.org/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/41883420662.pdfIn PDF document text
    • http://pc580.cn/upload_fck/file/2021-9-6/20210906192649203508.pdfIn PDF document text
    • http://krishikhabar.net/assets/ckfinder/core/connector/php/uploads/files/76424490388.pdfIn PDF document text
    • https://equimat-cheval.fr/file/13303786988.pdfIn PDF document text
    • http://www.mecateengenharia.com.br/ckfinder/userfiles/files/62957524796.pdfIn PDF document text
    • http://granitemountainranch.net/userimages/nawunudabijonigaketivuj.pdfIn PDF document text
    • http://bsa-billiard.by/images_from_html_editor/file/79593619408.pdfIn PDF document text
    • http://przyrodnik-kujawy.eu/userfiles/file/xedomafeviporobapugononim.pdfIn PDF document text
    • http://fantasymusic.it/userfiles/files/62729171283.pdfIn PDF document text
    • http://chpcentre.com/files/file/gorigugekusabanodoruxubi.pdfIn PDF document text
    • https://minervatech.work/js/ckfinder/userfiles/files/5160993218.pdfIn PDF document text
    • http://studiolegaletrotta.eu/userfiles/files/13514152767.pdfIn PDF document text
    • http://zhodnoceni-penez.cz/is/images/FCKeditor/File/wenosepox.pdfIn PDF document text
    • http://jfac.kr/ckfinder/userfiles/files/loluwiwuxegoje.pdfIn PDF document text
    • http://jedzenie365.pl/ckfinder/userfiles/files/35811553502.pdfIn PDF document text
    • https://forumhotel.by/wp-content/plugins/super-forms/uploads/php/files/gvcrpj57jlh8p05i00nhdagra5/51985806730.pdfIn PDF document text
    • http://hanasushichoice.com/uploads/files/11486956831.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=pay+matrix+pdf+odishaPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d804.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD804 10700 bytes
SHA-256: 371cfca4d638703743210ad45cd66a969c64cb1a621774a5ac27a1a2d099fb37
font_01_sfnt_off0000f097.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF097 18024 bytes
SHA-256: b037d7bbdccb32ae2af5f8d4c6be46e7b7bd24d76c84b10cb2a23810c9b14b2e
font_02_sfnt_off00011f8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F8A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1