Malicious PDF — malware analysis report

Static analysis result for SHA-256 c51b4c72d49498aa…

MALICIOUS

PDF

70.1 KB Created: 2021-10-02 20:30:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 08c9bbbb630ffe000d95777b51f39bb5 SHA-1: cb449d5a51057109023603ae7c5804a1a3483222 SHA-256: c51b4c72d49498aa34f7fb2511197f8485db432759c4eee70e94ac00c652fab1
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF exhibits characteristics of a phishing lure, including being image-heavy with a clickable action and containing numerous external links to potentially malicious domains. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs suggest it is designed to redirect users to malicious sites, likely for further exploitation or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9909

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
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 70 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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.
  • 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://infrive.ru/uplcv?utm_term=paper+chromatography+of+nickel+and+cobalt PDF link annotation
    • https://mercerapparelss.com/userfiles/files/lugatevoxer.pdfIn PDF document text
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ea13060a60---60141175323.pdfIn PDF document text
    • http://oldmotorsclub.com/files/file/kawidorimulajema.pdfIn PDF document text
    • http://bbhshipyard.com/userfiles/file/21068955289.pdfIn PDF document text
    • http://lotusburbank.com/uploads/files/12296944934.pdfIn PDF document text
    • https://cyklo-wellness-penzion-palice.cz/content/tejotaliruv.pdfIn PDF document text
    • http://schokoladenfontaene.de/idata/34048592766.pdfIn PDF document text
    • https://cryptoshift.be/anaeter_capital/siteadmin/userfiles/files/momifu.pdfIn PDF document text
    • https://meritumptt.pl/dokumenty/file/namixadezewabu.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/1613443f83cf95---80265789449.pdfIn PDF document text
    • http://mebco.ru/images/file/dojuripigibuzirit.pdfIn PDF document text
    • http://jtour.vn/userfiles/file/3604542079.pdfIn PDF document text
    • http://asu78.ru/userfiles/file/16795684528.pdfIn PDF document text
    • http://www.moyekolodin.com/files/64503527098.pdfIn PDF document text
    • http://vouchertiket.com/airplane/ckeditor/uploads/files/vatixoladegomibiwa.pdfIn PDF document text
    • http://etcpremium.com/userfiles/files/zudulu.pdfIn PDF document text
    • http://giayviettri.com/img-ftec/files/10153526732.pdfIn PDF document text
    • http://stihoplet.by/upload/editor/files/18540342174.pdfIn PDF document text
    • https://johanbjerke.se/userfiles/file/36954203977.pdfIn PDF document text
    • http://www.espace-hotelier.com/ckfinder/userfiles/files/lomufuruxifoku.pdfIn PDF document text
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/161374d2c10b28---pozatezoralowiza.pdfIn PDF document text
    • http://2016.letnifestiwal.pl/ckfinder/userfiles/files/57622445856.pdfIn PDF document text
    • http://elfuklid.cz/foto/Image/file/maxiwimifuzu.pdfIn PDF document text
    • https://saikekanglun.com/filespath/files/20210912195154.pdfIn PDF document text
    • http://domusanna.it/userfiles/files/8335702267.pdfIn PDF document text
    • http://koszyczarek.pl/userfiles/file/65065450171.pdfIn PDF document text
    • http://hycxchina.com/filespath/files/20210904041524.pdfIn PDF document text
    • 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_off0000b522.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB522 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cd39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD39 11244 bytes
SHA-256: 73386f6b2a1243072ef07fb794e83ad39ba1cf85644efbafb0970aced79ec294
font_02_sfnt_off0000e6f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6F6 14192 bytes
SHA-256: 1392bbb4c68ed9ca59c62864463715cc55087aea32060b9ae0a35d5951966419