Malicious PDF — malware analysis report

Static analysis result for SHA-256 94a835898896c4ba…

MALICIOUS

PDF

92.6 KB Created: 2021-07-01 00:08:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 02f202ed25a5f3d9099d82223c4dcf98 SHA-1: 3f2dbae179fadb64710e51a3612ac8660335681a SHA-256: 94a835898896c4baac776ceaeccaaa5ab6f75ab30c2d37aa70435d161116d57a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF identified as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many pointing to compromised CMS upload directories or disposable hosting, characteristic of a link farm used for phishing or malware distribution. The PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristic specifically highlights this malicious behavior.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9937

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://fullcolorspandoeken.nl/userfiles/file/fumukebepu.pdf
    • http://velocimapper.com//webfiles/file/94202024108.pdf
    • http://discarga.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5e5763d36---73720816816.pdf
    • https://glowskincare.net/wp-content/plugins/super-forms/uploads/php/files/d25790a396697daf20ed5936efdd3599/28132380029.pdf
    • http://auchli-appenzeller.ch/userfiles/files/3975949437.pdf
    • https://utilitydiscount.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5dd244ad2b---43013534393.pdf
    • http://ukrainski-rosyjski.pl/userfiles/file/wibejidefeferumotumaso.pdf
    • http://christopherdallo.com/file/83159341167.pdf
    • https://sandalyecenneti.com/wp-content/plugins/super-forms/uploads/php/files/0o9ka1cmfngufg9437jiek1c8c/xegepatidirewimame.pdf
    • https://jaiminsales.com/ckfinder/userfiles/files/puzeluxuk.pdf
    • https://mkting.com.co/wp-content/plugins/super-forms/uploads/php/files/a2752122ecf3508f7a301342969b1abb/wisetalinafo.pdf
    • https://hacunamatata.ru/wp-content/plugins/super-forms/uploads/php/files/3af387bd380cc48c85aa571d75018a15/34995111121.pdf
    • https://tongdaidoanhnghiep.com/app/webroot/upload/files/xonokede.pdf
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd74749600e---66902106623.pdf
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/160843d8906184---52275573969.pdf
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609252c4d8db9---sajevozitogekudizibe.pdf
    • https://balajitutorial.com/admin/userfiles/file/28420612899.pdf
    • http://ahdongjiu.com/upload_fck/file/2021-5-5/20210505105050818274.pdf
    • https://jamurgoreng.net/contents//files/91231767531.pdf
    • https://skazkavdom.com/wp-content/plugins/super-forms/uploads/php/files/75f881e4be6c878438e3baf072ce4ec3/giniruto.pdf
    • https://www.alarisusallc.com/wp-content/plugins/super-forms/uploads/php/files/4f7f91a5fef87012414455499772158d/lojalejelenubiwopiro.pdf
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/247vemaevn8635l4bhib6s7gs6/japabipa.pdf
    • https://2greenchicks.com/wp-content/plugins/super-forms/uploads/php/files/c5b45ce92f43156832ddaa3dcd813355/falikowimugejiwizuf.pdf
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a85e426a899---82595018338.pdf
    • https://marlin-aquarium.ru/ckfinder/userfiles/files/xirani.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=how+to+make+a+private+tf2+server+with+friends
    • 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_off000105eb.bin
80b3623dd48491ac1654df194a04ab4b860b75aaea9872d153d840267a51a073
pdf-font-stream PDF embedded font (sfnt) at offset 0x105EB 17368 bytes
font_01_sfnt_off00013333.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13333 16792 bytes
font_02_sfnt_off00014b4a.bin
f320e04e9c1fa59a5b845373845f8930afd3867a61c87701661aa40e8369e479
pdf-font-stream PDF embedded font (sfnt) at offset 0x14B4A 11072 bytes