Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5533be801c8dc7b…

MALICIOUS

PDF

97.5 KB Created: 2021-08-18 00:38:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 1d22368903646b11fa8118d6617fd485 SHA-1: 35d754d94a2b8951e7c2c1a588064ce61b2447e4 SHA-256: b5533be801c8dc7b71c89f26c5c512446bf8eff6e20e33d6504c00d48b63600e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains a large number of external links, many of which point to compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded URLs suggest a tactic of using link farms on disposable or compromised hosting to obscure the final malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

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://crewmak.ru/uplcv?utm_term=what+was+the+goal+of+pan-africanist+thinkers PDF link annotation
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f88da492395---tolefumovegowi.pdfIn PDF document text
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/3768glb0vma391mdonkj5h1n7j/kepizururikefel.pdfIn PDF document text
    • http://thegioidahoacuong.com/uploads/image/files/xanapejigulisuw.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/rbc566tv7id5rhsnb9bn2pqfvv/9337972470.pdfIn PDF document text
    • https://idea-web.ro/app/webroot/files/userfiles/files/joxilosexupivav.pdfIn PDF document text
    • http://www.schule.havonix.com/ckfinder/userfiles/files/71759514548.pdfIn PDF document text
    • http://celcg.pl/uploaded/file/sabilefefebagotujexu.pdfIn PDF document text
    • https://okinawa4d.com/contents//files/23310968511.pdfIn PDF document text
    • http://bigband-ulm.de/userfiles/files/ronebifibazidekul.pdfIn PDF document text
    • https://ingmarcomantovani.it/file/pawekijojozodakonidawola.pdfIn PDF document text
    • http://revucue.com/ckfinder/userfiles/files/degobajowiwizokekoru.pdfIn PDF document text
    • https://www.saltriot.com/wp-content/plugins/super-forms/uploads/php/files/451b68a8758af44c599e51490f4d6b30/68261227553.pdfIn PDF document text
    • https://nepalaviationmuseum.com/userfiles/files/darevoxanopira.pdfIn PDF document text
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/1608e47b2d3ecd---daterevegudegolad.pdfIn PDF document text
    • http://www.mywil.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16082aabec087f---xamuzevenifakufarowafo.pdfIn PDF document text
    • http://novosib-sport.ru/ckfinder/userfiles/files/80980954343.pdfIn PDF document text
    • http://scvumaichiramen.com/uploads/files/lujoze.pdfIn PDF document text
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/b320d388f0992361f8b48d5d07a9c618/lefovixonedepem.pdfIn PDF document text
    • https://www.hotel-restaurant-plainfaing.fr/ckfinder/userfiles/files/rafizip.pdfIn PDF document text
    • http://nprofit.hk/userfiles/gimibewafonajifojodaki.pdfIn PDF document text
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/16071d077b0ac9---rajesigewijopajuxebusur.pdfIn PDF document text
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077c04740226---vovotibuvosibanafox.pdfIn PDF document text
    • https://tims.ro/ckfinder/userfiles/files/82588889654.pdfIn PDF document text
    • https://mmagame.com/userfiles/file/84555001552.pdfIn PDF document text
    • http://beepost.vn/upload/userfiles/files/xuwefisefavasoxatajuwe.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_off00011912.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11912 17444 bytes
SHA-256: 510515ecc3f208094d51ea362abf41e55d4c95682a3aac210854b9f4a1917020
font_01_sfnt_off000145da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x145DA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00015df1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15DF1 10964 bytes
SHA-256: 724d12f332b4c28723ac36c1c6ce83d691987acf6965539ca4f0040170b8e7ec