Malicious PDF — malware analysis report

Static analysis result for SHA-256 3c3feafabfdeb9ec…

MALICIOUS

PDF

72.5 KB Created: 2021-09-06 14:22:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: a0418128356cb895a0c38f47278ec178 SHA-1: 2c4e3f46f58a8679e992d389bbf62e80299f1f41 SHA-256: 3c3feafabfdeb9ec40996bd92b37009fee0d1872471792aa38bda8a7a2b1ff84
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and an ML classifier, with heuristics indicating it functions as a link farm pointing to compromised CMS uploads and disposable hosting. While no scripts were extracted, the PDF structure and embedded URLs suggest an attempt to redirect users to malicious sites, likely for phishing or to download further payloads. The presence of multiple links to potentially compromised WordPress upload directories is a strong indicator of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/160889e99d7335---25043702790.pdf In PDF document text
    • https://bravo-hk.com/userfiles/file/jeromu.pdfIn PDF document text
    • https://augsburger-dartliga.de/uploads/file/guxaxanebupupibifesif.pdfIn PDF document text
    • http://bephoangdung.vn/uploads/ckfinder/files/sizukas.pdfIn PDF document text
    • https://kemxoithanhhang.vn/app/webroot/files/images/pages/files/2315549628.pdfIn PDF document text
    • http://bukhatirhomes.com/userfiles/file/simes.pdfIn PDF document text
    • https://spectrumohio.com/wp-content/plugins/super-forms/uploads/php/files/55843df1051e6439af392f2e2fd8af60/62339443757.pdfIn PDF document text
    • https://www.urban-quartz.co.uk/wp-content/plugins/super-forms/uploads/php/files/6b87bd77ae0cea1e62491b880cdb147e/noduv.pdfIn PDF document text
    • http://bluestandard.pl/ckfinder/userfiles/files/fajemop.pdfIn PDF document text
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/a0ff0c24f4a75b0d327eed6e71559ce2/59511179426.pdfIn PDF document text
    • http://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/itpquv8h749va2dqp2t9d19tf6/wamugejivupaluza.pdfIn PDF document text
    • https://traveltokiev.com/wp-content/plugins/super-forms/uploads/php/files/6s05qtvtdj7r1rcudrn1sc89e6/52668775573.pdfIn PDF document text
    • http://zhizhencn.com/filespath/files/20210823015831.pdfIn PDF document text
    • http://seigyobannkaigaikikaku.com/ckfinder/userfiles/files/68366188167.pdfIn PDF document text
    • http://ahchala.com/img/file/31605422843.pdfIn PDF document text
    • https://c4ir.ae/wp-content/plugins/super-forms/uploads/php/files/la5o1v5m97j69993phmer8sao2/4379857990.pdfIn PDF document text
    • https://sckprime.com/wp-content/plugins/super-forms/uploads/php/files/a265b93fea721cb7120694abecada6ee/mopebepifalakofi.pdfIn PDF document text
    • http://helloshoppingnepal.com/userfiles/file/ridotixebuvabezos.pdfIn PDF document text
    • https://www.growxponential.com/wp-content/plugins/super-forms/uploads/php/files/la7no50i510fbmekm2jvp9plvj/18228953338.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/161216caaa0c8c---bopetavolodugodarewevuvef.pdfIn PDF document text
    • http://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/b9bd1377d82c330cb6562151f12d7c45/nezejexeravazu.pdfIn PDF document text
    • http://csaladiegyteruautok.hu/userfiles/files/vokorisarubiso.pdfIn PDF document text
    • http://billedbutikken.dk/articlefiles/file/kowenugumazokakorud.pdfIn PDF document text
    • https://www.areatransfers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b80ae967c2b---11610834093.pdfIn PDF document text
    • http://worthingtonpark101.com/userimages/83849738835.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=kolmogorov+backward+equation+pdfPDF 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_off0000b93a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB93A 15836 bytes
SHA-256: 8eebb279f80eae44303710f3899f7999a371f699fc1d11104ecf91ad1791263b
font_01_sfnt_off0000e221.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE221 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fa38.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA38 11416 bytes
SHA-256: b3a6cedd257c0517b7eabecd48579a33e1346aa957e6d1d26311821274587838