Malicious PDF — malware analysis report

Static analysis result for SHA-256 35c835a418b4a90a…

MALICIOUS

PDF

69.0 KB Created: 2021-09-30 17:54:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: aa0d72d1467077aa1d553b77c3129d0b SHA-1: cd63950c3c1087f0b203d50b0d9f82770939f6f7 SHA-256: 35c835a418b4a90ac12a5a373ad85f328520df609c582c6c37a5229421c22599
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ClamAV and an ML classifier, with heuristics indicating it functions as a link farm. Multiple URLs extracted from the document point to compromised WordPress sites and disposable hosting, suggesting an attempt to lure users to malicious content. The document's structure and embedded URLs align with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 https://archism.ru/uplcv?utm_term=tor+android+browser PDF link annotation
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/1614de2d3787f3---kubakawomezagedopeza.pdfIn PDF document text
    • http://vuoncotichdep.com/upload/files/84793846364.pdfIn PDF document text
    • http://myphamlulanjina.com/upload/files/24966753776.pdfIn PDF document text
    • http://xutricolor.com/uploadfile/files/lanujoles.pdfIn PDF document text
    • http://primaria-ciocirlia.ro/media/file/97385403845.pdfIn PDF document text
    • http://geerhannutpourreussir.be/docs/upload/files/jetumupupezodonimezin.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/su3nseouiuvkr63nu461momt2i/gusilitexokinakegoresarus.pdfIn PDF document text
    • https://crcnueva.naturasoftware.com/uploads/images/files/petan.pdfIn PDF document text
    • http://yanartekstil.com/firma/files/josagorezevifilorekekogis.pdfIn PDF document text
    • https://biomisszio.hu/tmp/20365028269.pdfIn PDF document text
    • https://bhiringisamsankalimandir.org/ckfinder/userfiles/files/faloma.pdfIn PDF document text
    • http://hnc2.com/userfiles/file/vowuzetiwiveporimexalugog.pdfIn PDF document text
    • http://linklandhotels.com/upfile/editor/files/34175163243.pdfIn PDF document text
    • https://hanyauntuktesting.com/contents/files/waxuvosibalobod.pdfIn PDF document text
    • http://cpgny.com/userfiles/files/bexor.pdfIn PDF document text
    • http://www.motionmantra.com/userfiles/files/gijuvarulu.pdfIn PDF document text
    • https://www.delaneyllc.com/ckfinder/userfiles/files/xerigusurolabulusat.pdfIn PDF document text
    • http://cold.lt/userfiles/file/bojokaxikoladoz.pdfIn PDF document text
    • https://kingdomdatesuae.com/userfiles/files/lafupopejugotimuk.pdfIn PDF document text
    • https://baconbites.com/wp-content/plugins/super-forms/uploads/php/files/v5tqqumnod5786jhm37q8hi8o2/wogunija.pdfIn PDF document text
    • http://nj-rshb.com/v15/Upload/file/20219121452117801.pdfIn PDF document text
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/s9mp8buohc4rluh06cb9p04et4/vedefubuvuwedolizerageru.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16145561433d5a---luxonudefuvis.pdfIn PDF document text
    • https://www.asoriofrio.org/ckfinder/userfiles/files/webitebegarasivoramakud.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_off0000b05a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB05A 10284 bytes
SHA-256: a395b67b6003f3e9828bf0f4204b667f6fa7473231295e0a3073ca1aa18a8148
font_01_sfnt_off0000c7a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7A4 15420 bytes
SHA-256: b67b74139fc4e8e3941a5164be9428b2d264804f2aa7d89c4b6941f6feb3779b
font_02_sfnt_off0000eedf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEDF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1