Malicious PDF — malware analysis report

Static analysis result for SHA-256 536b7f51bac0efc6…

MALICIOUS

PDF

70.3 KB Created: 2021-09-18 03:58:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 4b9e4f379d4da89fa1f6067f8443531e SHA-1: 4adc0d48020f69a073131696f3429d58ea46c597 SHA-256: 536b7f51bac0efc6707d96872066de439abfaa683220ed91bbd95c1c0ad1038a
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external links, many pointing to compromised WordPress upload directories or disposable hosting, suggesting it functions as a link farm to distribute malicious content or phish users. The PDF structure and link farm heuristics strongly indicate a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9909

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://laborke.ru/uplcv?utm_term=conjuring+the+devil+made+me+do+it+movie+online PDF link annotation
    • http://kondicionery-noginsk.ru/upload_picture/file/sizemebonoxunufaj.pdfIn PDF document text
    • https://ripedzn.com/app/webroot/files/fckeditor/file/62029207957.pdfIn PDF document text
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c0a0be107a---nudalamotixan.pdfIn PDF document text
    • https://kaptenhoki.info/contents/files/88676214358.pdfIn PDF document text
    • https://namastehealth.in/wp-content/plugins/super-forms/uploads/php/files/o4q86rtc16a74qmmj0u8vetcok/tezogadiladoso.pdfIn PDF document text
    • http://xn--2osv9pt2jfpt.com/uploadfiles/files/80279799004.pdfIn PDF document text
    • http://degrossier.nl/uploads/file/pimovebadi.pdfIn PDF document text
    • http://bfr-bialapodlaska.pl/userfiles/file/31675471271.pdfIn PDF document text
    • https://f1com.ge/wp-content/plugins/super-forms/uploads/php/files/0c4347fa5efad898e5150f166d89203b/sexelaper.pdfIn PDF document text
    • https://radio-clipa.ro/userfiles/file/vuxowuwuvugalagab.pdfIn PDF document text
    • http://www.verneteco.com/ckfinder/userfiles/files/11630234526.pdfIn PDF document text
    • http://matrixuniverzum.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16140a858dc7a9---71177269437.pdfIn PDF document text
    • https://oilbasaro.com/web/images/ckfinder/files/20210913163541.pdfIn PDF document text
    • http://casinodanmarkjackpot.dk/userfiles/file/mugozozaxexutuvas.pdfIn PDF document text
    • http://moestuinwebshop.nl/userfiles/file/15739213594.pdfIn PDF document text
    • http://asvpp.fr/pdf/rekivazekowumas.pdfIn PDF document text
    • http://chandravanshi.com/userfiles/file/47083620870.pdfIn PDF document text
    • http://worldofpacifiers.com/editor_uploads/system/files/76464337782.pdfIn PDF document text
    • https://ln80.cn/filespath/files/20210910203148.pdfIn PDF document text
    • http://playonathletics.com/userfiles/file/kisibovutigelanivimuvo.pdfIn PDF document text
    • http://stihoplet.by/upload/editor/files/fimoboxiwavizozeken.pdfIn PDF document text
    • http://ar-intl.net/wp-content/plugins/super-forms/uploads/php/files/4a9vdnjetqai152gg462ekp1d5/saxanivovakinatemibiladi.pdfIn PDF document text
    • https://deconkhoemanh.com/wp-content/plugins/super-forms/uploads/php/files/5d6sqg7icjqgv5mclf9pham67g/49721095749.pdfIn PDF document text
    • http://elcivan.com/admin/UserFiles/file/pigolol.pdfIn PDF document text
    • https://corpus.bg/files/fck/file/jepopa.pdfIn PDF document text
    • http://85560891.com/upfolder/e/files/20210916204908.pdfIn PDF document text
    • https://soportedevida.mx/ckfinder/userfiles/files/35922103555.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_off0000b6a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB6A7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cebe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEBE 10856 bytes
SHA-256: 49ecd3a822ad4d5ac4fe1fcfd99578bb71c27a9f877e3f41c3d90644bc1daee9
font_02_sfnt_off0000e75b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE75B 14520 bytes
SHA-256: 4ae59e046de46b8b92ab1ee0a1d24f133996280dcc3ed8c601e02f07f69b6467