Malicious PDF — malware analysis report

Static analysis result for SHA-256 c3d4ff37f6430951…

MALICIOUS

PDF

80.9 KB Created: 2021-09-21 09:38:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 8d3629dbaa557389902f2c2ffe950088 SHA-1: 025ca3b719a70755365a776d939c15356175c84b SHA-256: c3d4ff37f64309514ed1132b1dd342f1257393270fd2f85a9f6c08124a98ab0e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised CMS upload storage or disposable hosting, indicating a link farm designed to redirect users to malicious sites. The presence of external URIs and a link farm structure strongly suggests an attempt to lure users to external resources, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 http://studiorestagno.eu/userfiles/files/98466038801.pdf In PDF document text
    • http://kojeneckezbozi.eu/userfiles/file/goloziwozewilugikawo.pdfIn PDF document text
    • http://ohmytour.kr/FileData/ckfinder/files/20210909_16949B9C9186DD13.pdfIn PDF document text
    • https://tsegypt.com/file/5226382786.pdfIn PDF document text
    • https://arrayamed.com/userfiles/file/jijuxabopanu.pdfIn PDF document text
    • http://ajtoablakcentrum.com/_user/file/mazevopevi.pdfIn PDF document text
    • http://alfavs.eu/userfiles/file/43727418316.pdfIn PDF document text
    • http://www.azurwelcomeservices.com/userfiles/file/dediwipufijimigo.pdfIn PDF document text
    • http://remproekt-m.ru/admin/ckfinder/userfiles/files/bubowakigorelumisofuju.pdfIn PDF document text
    • http://caycanh.vn/images/fck/file/14412941486.pdfIn PDF document text
    • https://gestionarival.com/userfiles/file/28410389507.pdfIn PDF document text
    • http://fullcolorspandoeken.nl/userfiles/file/wajixarivarazu.pdfIn PDF document text
    • https://www.pepinieres-gey.fr/ckfinder/userfiles/files/zujipe.pdfIn PDF document text
    • http://www.cargeacrew.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614090a5b49a1---wozodopeginutuvevofolew.pdfIn PDF document text
    • https://minipowerpack.net/upload/files/3905147898.pdfIn PDF document text
    • http://heathrowairporttaxi.website/userfiles/file/56239140545.pdfIn PDF document text
    • http://webcertain.asia/contentupload/fckeditorUploads/organization_/file/demunojore.pdfIn PDF document text
    • http://engcaphone.com/_UploadFile/Images/file/wezamubilixanaripokexuzeg.pdfIn PDF document text
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16145fb8c391d9---74382947137.pdfIn PDF document text
    • http://sp3siemianowice.pl/userFiles/files/45541418530.pdfIn PDF document text
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613c31e7ee979---43426173714.pdfIn PDF document text
    • http://koovappadyscb.com/ckfinder/userfiles/files/bilagudatemugulom.pdfIn PDF document text
    • http://xn--80aaae7amexjfdlfdfg.xn--p1ai/files/file/38486218918.pdfIn PDF document text
    • https://marathonroller.com/userfiles/files/gelima.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=how+to+ban+websites+on+your+phonePDF 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_off0000d8c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8C9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f0db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0DB 17152 bytes
SHA-256: d8867acaa61546a8c01d2a46826dc7d3629885d2a185111bf94d5c8d8343ec1b
font_02_sfnt_off00011d46.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D46 10732 bytes
SHA-256: 054c5210bc7155474f2e76ce88e562cfede391c63a69d7613625f6a93531ea32