Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f9ad559dd68ce9c…

MALICIOUS

PDF

106.2 KB Created: 2021-07-03 06:27:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2026-06-05
MD5: 744d72327d048cc4fdb6487905b5716b SHA-1: fbfdf4096f1e8612a3dda895392e97e341b6dda8 SHA-256: 3f9ad559dd68ce9c899d6f008d43e843c3ba32c31c96b02043e27259ba7d7742
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, pointing to numerous URLs hosted on compromised CMS uploads, likely to obscure the true destination and evade detection. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the overall structure suggests a phishing or redirection attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

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://vakukh.ru/wp-content/plugins/super-forms/uploads/php/files/019c6ee2b86a3fb8c8dbf2a5c89113a7/33897495608.pdf In PDF document text
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7fd91d33de---3455516194.pdfIn PDF document text
    • https://youstore21.com/wp-content/plugins/super-forms/uploads/php/files/d15cd5410e353b4667a4f6236f8b6f48/mezunogow.pdfIn PDF document text
    • http://bpsstudio.hu/uploads/vojaxonu.pdfIn PDF document text
    • https://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/q50dtecjprmt267ujql70mp1ja/38913380588.pdfIn PDF document text
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/1607bb3bfe8996---28857533252.pdfIn PDF document text
    • https://alihuata.com/userfiles/file/88352053502.pdfIn PDF document text
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bc472fe4d0e---63150270244.pdfIn PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160918ad08f6e8---29115229845.pdfIn PDF document text
    • https://www.3dreamchurch.com/wp-content/plugins/super-forms/uploads/php/files/5beaa7dc0b28c5d4d9e149811a863910/3486128402.pdfIn PDF document text
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607627bb5bc5f---85072908419.pdfIn PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/1607b83f368ab9---29176034326.pdfIn PDF document text
    • http://huile-de-nigelle.info/userfiles/file/kijamulu.pdfIn PDF document text
    • http://cs-golfclub.com/ckupload/files/2561272748.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=the+price+elasticity+of+demand+is+defined+asPDF link annotation
    • 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_off00013878.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13878 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001508f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1508F 10960 bytes
SHA-256: 82aff1b932a3444e1afec8639645db47e7572610689978696f04b59d65bf30a6
font_02_sfnt_off000169d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x169D4 18204 bytes
SHA-256: ff38102606f5dbcacdd2d82f09391f49520acfd3902aefedd647cee81ebb570b