Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef2bec3761d581ae…

MALICIOUS

PDF

75.6 KB Created: 2021-09-03 22:18:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 521022d42e3f0141c9ba4649eb9f51aa SHA-1: 851b6fdaeec6486215cc98646e98ef218673c04e SHA-256: ef2bec3761d581ae44d2a15faf844ff5d8a69dd8f001b9d680fa0c28486d59e5
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous links, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The document body is heavily obfuscated and unreadable, providing no direct content clues, but the overall structure and URL analysis strongly indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://huntic.ru/uplcv?utm_term=identifying+participial+phrases+worksheet PDF link annotation
    • https://mosconi.net/userfiles/file/fanesizalagumomurarok.pdfIn PDF document text
    • http://fantasymusic.it/userfiles/files/47193660833.pdfIn PDF document text
    • https://sofanet.ro/ckfinder/userfiles/files/34948405313.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d3e6f117f7---41615832830.pdfIn PDF document text
    • http://vincityhomes.vn/wp-content/plugins/super-forms/uploads/php/files/ouf6bkibnqrtfgb56p669bdtbq/filogi.pdfIn PDF document text
    • http://www.scsk12.org/policy/files/files/kapivamibofax.pdfIn PDF document text
    • http://geodeslaboratori.eu/userfiles/files/ritikanexukobajujesuwizog.pdfIn PDF document text
    • https://bbensonmft.com/wp-content/plugins/super-forms/uploads/php/files/e43689f63e55e49b8c83f4ed5fe2b018/dexezusukomivepamake.pdfIn PDF document text
    • https://whitelightdesign.com/wp-content/plugins/super-forms/uploads/php/files/e5fcbfb8d364135597ba17d1a3577865/11650321521.pdfIn PDF document text
    • http://nuyewrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/94dbf5f735beaae7fb641ce52da93bc0/78024045066.pdfIn PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/22835712e3966003f540688a386a0225/74200940210.pdfIn PDF document text
    • http://hoteldanang.vn/uploads/images/files/dojiluwakota.pdfIn PDF document text
    • http://orourkelawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/gosunidojoxaparutevu.pdfIn PDF document text
    • https://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/at2k1f8204qi2i585pcep5u1kq/16740860851.pdfIn PDF document text
    • https://www.espymetcalf.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d031332df48---jojatitovutuxugus.pdfIn PDF document text
    • http://guowangcable.com/d/files/58376212403.pdfIn PDF document text
    • http://alexandercdg.com/clients/36029/File/segogabovigip.pdfIn PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1609d0b471fd48---zuvebalanu.pdfIn PDF document text
    • https://aokman-drive.com/d/files/lugelolapif.pdfIn PDF document text
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/26e44372fc26b3616eb2bde6b6a37f8c/88946020890.pdfIn PDF document text
    • http://tragadsonisurat.com/ckfinder/userfiles/files/60972109326.pdfIn PDF document text
    • http://adirondackseafood.com/ckfinder/userfiles/files/bupekadu.pdfIn PDF document text
    • http://dhleisure.com/ckupload/files/2407720975.pdfIn PDF document text
    • https://pypconsultores.mx/userfiles/file/durux.pdfIn PDF document text
    • http://dansensvenner.dk/imagesfile///gamoriguwuvizox.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_off0000c4a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC4A9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dcbb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCBB 16392 bytes
SHA-256: 27eca23074498d828ccb5d59beeb1ec3a7dcfade500b5d3bf5ba5ee703100330
font_02_sfnt_off00010667.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10667 11140 bytes
SHA-256: 68d8eee59c58f93aa16f0450a29174177fecfdca3c126bc9e1dbe8744cd016eb