Malicious PDF — malware analysis report

Static analysis result for SHA-256 39ac4ada99fc2a3b…

MALICIOUS

PDF

95.5 KB Created: 2021-06-26 14:07:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a9897c4f1fb067a3b48323f145ac028d SHA-1: 1e44b16855675f0b58547d6949c2ddcc9b8ea235 SHA-256: 39ac4ada99fc2a3bc09196f6da22475d2e3378a4d1d065b8fc72f793c7e80115
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous external URIs and links to compromised WordPress upload storage, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest 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, potentially harmful, sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9786

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://infrive.ru/uplcv?utm_term=harvest+moon+ds+celia+marriage+guide
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/16076f0231dd61---10659777087.pdf
    • https://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/97f7b035b7960caf753bb7748e6f4ca8/30863591879.pdf
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/fjt7jh93ktsnpk4ujvk93b4epa/nuzewegukupu.pdf
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/160739071be987---gabamiwavogumozituloga.pdf
    • https://www.skyline-recruiting.com/wp-content/plugins/super-forms/uploads/php/files/eac1f9df6c8c8e5eeefb67bba1aebce4/68337207397.pdf
    • http://casaledellasignora.it/userfiles/files/pezoso.pdf
    • http://www.expertnutritionadvisor.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609644e3a6d72---ravuvezuvamulewinekizis.pdf
    • http://castanienfamily.com/clients/74558/File/pinuxafimiromovora.pdf
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a4470d5c496---vaniguwijubatibewovufage.pdf
    • http://africa-emergence2019.com/userfiles/file/xeduxak.pdf
    • https://repare-ton-smartphone.com/userfiles/file/memazajodireno.pdf
    • https://archcosmeticstudio.com.au/wp-content/plugins/super-forms/uploads/php/files/3ed54f860013ff1822bd73172d2fd474/xubusid.pdf
    • https://yarpaket.ru/userfiles/file/malekevuxawidolota.pdf
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093c950596ce---37628451453.pdf
    • http://mintaialuminum.com/d/files/2019502166.pdf
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b17c8e8f56---wuloxetosaguzatizesite.pdf
    • http://handbook.hu/upload/page/file/52162826216.pdf
    • http://bookblog.kr/data/file//files/wasilunurago.pdf
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/a2631b949d931f40a2accd7dcf20e0bc/80097873829.pdf
    • https://www.aironface.com/wp-content/plugins/super-forms/uploads/php/files/d8f29ff70d5a91987361a5674e31c611/67872698635.pdf
    • http://morgancountyoh.com/userimages/65235821300.pdf
    • http://ophirtonhotel.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16094145035390---zovuxuxux.pdf
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608043a377608---6408703828.pdf
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16085b1d480c54---basazobajubodowijituro.pdf
    • https://fanaf.comarticle_ressources/file/37725601833.pdf
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/fu32jttubcf3nt4lmc9fmiomg9/surejudeguno.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ffce.bin
96c4c609610bf1c8695239d7270e856c03b042f83a9a8ec3eb440bd489261e8c
pdf-font-stream PDF embedded font (sfnt) at offset 0xFFCE 3952 bytes
font_01_sfnt_off00010f28.bin
1bb87b40bb5ac25665cba362fc982758dd5a3046cb892e089f3a71be35a42feb
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F28 10872 bytes
font_02_sfnt_off00012801.bin
99ff4521d93f59ecbd20882eff6b267f5bad420b6d644ba1f0f400eca70f0ab2
pdf-font-stream PDF embedded font (sfnt) at offset 0x12801 18756 bytes
font_03_sfnt_off000157c8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x157C8 16792 bytes