Malicious PDF — malware analysis report

Static analysis result for SHA-256 4e8f4bdbd56b3ba8…

MALICIOUS

PDF

87.4 KB Created: 2021-06-27 04:44:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 3e535663a2e64141ad2563f8cfc4df09 SHA-1: 2d1a526435bc031b3878cfad136fe3902fa6b484 SHA-256: 4e8f4bdbd56b3ba87433d1a25c5dc3731cc83ca9421db22961c496c03866985f
156 Risk Score

Malware Insights

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

The ML classifier and ClamAV both strongly indicate maliciousness. The PDF contains numerous links pointing to compromised WordPress sites, suggesting it's part of a link farm designed to distribute malicious content or phish users. The presence of multiple external URI heuristics further supports this attack pattern.

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://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609fbcee61515---difuvotatukawaf.pdf In PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160920052e368f---dopabomejujeka.pdfIn PDF document text
    • https://consurs.ro/ckfinder/userfiles/files/gumer.pdfIn PDF document text
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a06f8631fc---munuzepep.pdfIn PDF document text
    • http://imssp.by/data/images/fxeditor/file/josamowejulo.pdfIn PDF document text
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/cfd38288c932884307d2897a0c7907cc/botakojikov.pdfIn PDF document text
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160853a873de79---51630013329.pdfIn PDF document text
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c98b94cdf1c---26369633618.pdfIn PDF document text
    • https://jollytime.ru/wp-content/plugins/super-forms/uploads/php/files/7d99ac36ccd031e4ec8260938cc14047/zorobogulujenuno.pdfIn PDF document text
    • http://bobas24.pl/Upload/file/22076219936.pdfIn PDF document text
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160d0880906e15---11428661790.pdfIn PDF document text
    • https://primax.fr/wp-content/plugins/super-forms/uploads/php/files/rlr5i62uqd8ue6um7agqe1nnd2/pigakirafaloxamojiref.pdfIn PDF document text
    • http://www.petersmetalstitching.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160be6eff6a4f9---gepusesijalovijuxewu.pdfIn PDF document text
    • https://butchercurnow.com/img/shop//contents/42882385431.pdfIn PDF document text
    • https://www.oneirishrover.com/wp-content/plugins/super-forms/uploads/php/files/db45027fbaaf28de2dfa0600980b2237/1607697197.pdfIn PDF document text
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/160719fd344ba5---kifobixakapagixezo.pdfIn PDF document text
    • https://ddshower.com/ckfinder/userfiles/files/sojowa.pdfIn PDF document text
    • http://cesurmakina.com/userfiles/file/bijilikivogezofeviremirak.pdfIn PDF document text
    • https://blackknowledge.com/wp-content/plugins/super-forms/uploads/php/files/96e1deaecaba67d5827026f27ac1b8dd/nekesijapari.pdfIn PDF document text
    • https://nailseasupportgroup.com/wp-content/plugins/super-forms/uploads/php/files/a99ab6421820819398ec2bd1fe177a1b/dazexalofikaxaperokovozoz.pdfIn PDF document text
    • http://dnepropress.net/files/file/domuw.pdfIn PDF document text
    • http://urbancollab.com/userfiles/Proj_Name//files/57112063129.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608637e24cfea---wadibetuna.pdfIn PDF document text
    • https://cvenhancer.com/wp-content/plugins/super-forms/uploads/php/files/559a08c823a3ec202905955715625895/68649337835.pdfIn PDF document text
    • http://walthamclassof1985.com/clients/5/52/52060312c10aa816a718e90a19a6a7a1/File/17545585307.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=driving+distance+between+2+pointsPDF 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_off0000f233.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF233 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010a45.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A45 16996 bytes
SHA-256: 9bdebcaf8ad69a1d45ba5079018c84c8fd9de78a3158dffa287a9527c6b82247
font_02_sfnt_off0001369e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1369E 11056 bytes
SHA-256: c7610b7bbd7411c09ce9d6c38aa80ea0443df826649eeadda249048dac7cdabb