Malicious PDF — malware analysis report

Static analysis result for SHA-256 19b969d0b9b3f534…

MALICIOUS

PDF

88.8 KB Created: 2021-07-17 16:33:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0474256bb78b5a9ca4034a8dc0490e87 SHA-1: 7989b154aa1469cb4be373897ecfa86e79ca6b4f SHA-256: 19b969d0b9b3f53469aab3ec5477cf6246b94cb2e22178db417b6517ef5d1956
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. Although no scripts were directly extracted, the PDF structure and link farm heuristic point towards an attempt to exploit users via external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 https://chiuman-hk.com/images/file/vobikixumowogagexenuxi.pdf
    • http://studiotecnicoarduini.eu/userfiles/files/35997926644.pdf
    • https://kozhikodedeaf.org/admin/my_files/file/susofuziginilolamedu.pdf
    • https://www.themeshcowork.com/wp-content/plugins/super-forms/uploads/php/files/7676e3f12aa3ec3dbba06940220be9c9/47719972673.pdf
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf61ec3f714---mezuzokadanenazora.pdf
    • https://investmentskillsgroup.com/images/userfiles/file/zokedijudubejebes.pdf
    • http://anandtouristcorporation.com/uploads/mokit.pdf
    • http://www.ambredore.com/wp-content/plugins/formcraft/file-upload/server/content/files/160829ad062f88---xedarebizobo.pdf
    • https://rclurie.com/wp-content/plugins/super-forms/uploads/php/files/852720c3be7f4cf83cd4cbe81c556226/nunodavebematupak.pdf
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160ad02d1f1500---65758697269.pdf
    • https://rimsball.com/ckfinder/userfiles/files/7869368450.pdf
    • http://kehlux.lu/userfiles/files/tadavonedi.pdf
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160e3a8ebe891d---44580863832.pdf
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16082fa9ed5149---kopimiwobukuda.pdf
    • http://nissanotogovap.net/uploads/images/files/tesetizuvep.pdf
    • https://ilc.ua/wp-content/plugins/super-forms/uploads/php/files/e7fakrjtovrjmfp2npu8q2t2i3/94897576829.pdf
    • https://decoveinvestment.com/userfiles/file/8048617283.pdf
    • http://weberstellen.ch/userfiles/file/60233992553.pdf
    • http://flambotour.it/themes/userfiles//files/22533452677.pdf
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160790a7844d3b---14264741638.pdf
    • http://ibnuaffan.com/ckfinder/userfiles/files/39895102037.pdf
    • http://kenzoum.org/home/integrity/public_html/ckfinder/userfiles/files/5354013969.pdf
    • http://rsst77.ru/upload/files/ropewosajo.pdf
    • http://resetimpianti.it/reset/public/file/xinavibizevutefupuf.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=people+are+in+your+life+for+a+season
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f79c.bin
4b3292b6b8894d563c6832719a89b2766c2ce9b194d75b3797cb050993e4e540
pdf-font-stream PDF embedded font (sfnt) at offset 0xF79C 10468 bytes
font_01_sfnt_off00010f7c.bin
27542c531256ed2661ee77532cf030f6498dc334c87246effd87779c6c61e743
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F7C 17540 bytes
font_02_sfnt_off00013d84.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13D84 16792 bytes