Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f90affc1fce58d7…

MALICIOUS

PDF

80.6 KB Created: 2021-09-12 19:59:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: fb28349243abf1d7c10d632a927717b4 SHA-1: eb08339c7d8c3a966a1016acc9eed410f9dfc527 SHA-256: 8f90affc1fce58d79d08aefe0ac4efda6a56517a978620ebde1e6df70afb9b36
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs that form a link farm, with many pointing to compromised websites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and embedded links are indicative of a malicious document designed to lure users to external, untrusted sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://ketchas.ru/uplcv?utm_term=army+men+rts+android PDF link annotation
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/q893ko23mdvrk0o4m5jric11h7/13463881793.pdfIn PDF document text
    • http://nexxstep.nl/userfiles/file/pegavavazolopaxogi.pdfIn PDF document text
    • http://artdealer.vn/upload/fckimagesfile/62a3342894c4a1320fed26696f126f5c.pdfIn PDF document text
    • https://fokusmedia.com/images/uploads/lufumilana.pdfIn PDF document text
    • https://www.le-domaine-de-hauterive.fr/ckfinder/userfiles/files/jusuxedamedalif.pdfIn PDF document text
    • http://synphabase.ch/upload/file/53346103741.pdfIn PDF document text
    • http://optimaglobal.net/ckupload/files/6901050970.pdfIn PDF document text
    • https://incense888.com/uploads/files/202109041256582971.pdfIn PDF document text
    • http://cgl.lu/userfiles/files/30121324795.pdfIn PDF document text
    • http://steelfurniturecn.com/d/files/5605579869.pdfIn PDF document text
    • https://inchirierielicopter.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1612f19ac1f283---zukevurijopub.pdfIn PDF document text
    • http://mientrungland.net/uploads/image/files/59107803136.pdfIn PDF document text
    • https://pbpkrosno.com/fckfile/46718985948.pdfIn PDF document text
    • http://dreesmann-foto.de/userfiles/file/noranewetawesipunisalak.pdfIn PDF document text
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/572da2756be8f28a53218dff73af392d/65321955612.pdfIn PDF document text
    • http://uralteplostroy.ru/content/file/93952597641.pdfIn PDF document text
    • https://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/q94s98ull4bvods7kjvu9i5qji/sozisopoxesa.pdfIn PDF document text
    • http://jandebruijn.com/uploadimages/files/37961075797.pdfIn PDF document text
    • http://i-daa-wl.de/userfiles/vikegukodade.pdfIn PDF document text
    • http://interreg-ipa-husrb.com/downloads/jivol.pdfIn PDF document text
    • https://gornjastubica.hr/files/8502750473.pdfIn PDF document text
    • https://malashealthcare.com/userfiles/files/kufiwowobepes.pdfIn PDF document text
    • http://cgemfoco.com.br/ckfinder/userfiles/files/nawekefewavukubum.pdfIn PDF document text
    • http://j1ent.com/userfiles/file/20210911002754.pdfIn PDF document text
    • http://anhuifan.com/upload_fck/file/2021-9-2/20210902042346282118.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_off0000d5e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5E0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000edf2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDF2 18144 bytes
SHA-256: 9845dc8ac3d5ea50442a36b8f1ee0bcfc6952b757d065eaa19cf72cd261a4406
font_02_sfnt_off00011d7b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D7B 10460 bytes
SHA-256: 8adb406f8df0ec6d38cf5568a7abf00e569f48c2f361ab8db9e5f4d07eb06073