Malicious PDF — malware analysis report

Static analysis result for SHA-256 471de168755a554d…

MALICIOUS

PDF

98.2 KB Created: 2021-10-13 20:26:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: f069a16df3d454c54b7904de5b2ceb0b SHA-1: abdd227d0489ed21112a03e0c2d6e0aec0e1752b SHA-256: 471de168755a554d8a3cab498cb0a1f006f641d1ea107b262c9c688c0f06da7c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of external links, many pointing to PDF files hosted on various domains, some of which are flagged as compromised CMS upload storage or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution by luring users to click on these links. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the link farm structure and heuristic findings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 http://ccsl.asia/files/xuzatotigevabez.pdf In PDF document text
    • http://kag.fr/userfiles/file/57899231647.pdfIn PDF document text
    • https://andhimazhai.com/images/files/wizuj.pdfIn PDF document text
    • https://snowcat.pl/admin/ckfinder/userfiles/files/gukalapirataneso.pdfIn PDF document text
    • http://www.rpv-drachten.nl/files/file/fogagekalipugovulumim.pdfIn PDF document text
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/88de08cdf42bc2e8ebf015aa8a8a4a47/wujifexifo.pdfIn PDF document text
    • http://www.papelerialapiceros.es/ckfinder/userfiles/files/mufudiki.pdfIn PDF document text
    • http://nhahanghienminh68.com/upload/files/63774578959.pdfIn PDF document text
    • https://pharma-tools.eu/galeria/file/jadob.pdfIn PDF document text
    • https://totounited.com/contents/files/pizitimuresonixelesuk.pdfIn PDF document text
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/1615c2694e104e---7609817869.pdfIn PDF document text
    • https://lllk.ru/wp-content/plugins/super-forms/uploads/php/files/e67b0ca149bc6a98dae79a30cc736486/kowuletodofokizolewizoze.pdfIn PDF document text
    • https://greenvalleykerala.com/ckfinder/userfiles/files/nurejugipiz.pdfIn PDF document text
    • https://iieng.org/editor/ckfinder/userfiles/files/93734196149.pdfIn PDF document text
    • http://internet-trade.cz/UserFiles/file/31880150377.pdfIn PDF document text
    • http://halmar.info/userfiles/file/zoxodaneb.pdfIn PDF document text
    • http://evaemlak.com/userfiles/file///komatinemevozigidadawo.pdfIn PDF document text
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ffd106c87b---96355991010.pdfIn PDF document text
    • https://miet.hu/kepek/24295497781.pdfIn PDF document text
    • https://latrinquette.com/upload/editor/file/99293547864.pdfIn PDF document text
    • https://aokman-drive.com/d/files/31194894908.pdfIn PDF document text
    • https://dusunceokulu.net/resimler/files/46511183692.pdfIn PDF document text
    • http://feedproxy.google.com/~r/Xvkpad/~3/xPAns0MRe5M/uplcv?utm_term=best+practices+for+taking+meeting+minutesPDF 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_off00011558.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11558 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012d6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D6A 19616 bytes
SHA-256: 189285a9677c0c47d19b9d69790250b56b0e69edcc57851d34cc60df173aa738
font_02_sfnt_off00016124.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16124 11024 bytes
SHA-256: b8ef29e19e883e91c02817feffe3486036ce7941f67f91503333222f3813166b