Malicious PDF — malware analysis report

Static analysis result for SHA-256 ea4971bfa1543138…

MALICIOUS

PDF

75.7 KB Created: 2021-09-20 10:33:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: c9782f3b07744d3a22c63d6913812d74 SHA-1: cac999a886e98ba23255da59a33a5e2a35b552da SHA-256: ea4971bfa15431385485f39f9fcfda7d7381ec74a7f64c2f2bdc1533c5cd40a0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains multiple PDF link farm heuristics pointing to compromised WordPress sites and disposable hosting, suggesting a phishing or redirection scheme. Although no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of an attempt to lure users to malicious content, likely for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/c7b5b4cb439f0ef7313a0f5159f449e1/29759797973.pdf In PDF document text
    • http://xn----9sbkvfu2aex3d.xn--p1ai/ckfinder/userfiles/files/rekurivifasa.pdfIn PDF document text
    • http://postelezmasivu-brno.com/ckfinder/userfiles/files/62896011473.pdfIn PDF document text
    • http://dakdekkersindex.nl/images/uploads/buxutinok.pdfIn PDF document text
    • https://turkuazhost.com/calisma2/files/uploads/jowovelulagalivose.pdfIn PDF document text
    • http://immobiliareborghi.com/userfiles/files/24180423572.pdfIn PDF document text
    • http://lirealestatelitigator.com/wp-content/plugins/super-forms/uploads/php/files/03807bb5aa7e1a83b3d25e5d81c8dcaa/65857214586.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133f3d2d0891---kipiv.pdfIn PDF document text
    • https://casabresciani.it/uploads/file/xukomumebididaga.pdfIn PDF document text
    • http://lnaixi.com/userfiles/file/20210916032142_770257080.pdfIn PDF document text
    • http://chinatriage.com/ckfinder/userfiles/files/xuwanokixipafova.pdfIn PDF document text
    • http://kool-house.com/upload/editor/file/54931601212.pdfIn PDF document text
    • https://chingchia.com/uploads/files/202109051807039118.pdfIn PDF document text
    • https://www.aukuras.org/ckfinder/userfiles/files/75553275275.pdfIn PDF document text
    • http://reklama-v-sochi.com/ckfinder/userfiles/files/99058800484.pdfIn PDF document text
    • https://www.abandassociates.com/ckfinder/userfiles/files/xunawota.pdfIn PDF document text
    • http://cameralehiep.com/hinhanh_fckeditor/file/62473897825.pdfIn PDF document text
    • http://petraifevronii.ru/ckfinder/userfiles/files/76259671460.pdfIn PDF document text
    • http://www.santabriganti.org/admin/ckfinder/userfiles/files/38947983074.pdfIn PDF document text
    • https://www.nvsrolko.org/ckfinder/userfiles/files/selariwedotajusesas.pdfIn PDF document text
    • https://searchkar.com/ci/userfiles/files/mozupiwesivufilolegi.pdfIn PDF document text
    • http://topp.pl/_topp/file/betotapajexifotorigu.pdfIn PDF document text
    • http://psychologkmalinowska.pl/ckfinder/userfiles/files/38411634121.pdfIn PDF document text
    • http://otpetye.com/images/shared/file/56295477003.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=come+to+jesus+lyrics+and+chordsPDF 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_off0000c267.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC267 11008 bytes
SHA-256: 2b78739406bdf4986080f1ddccb102e5267a4dc5c137dbdf6a37cda9b0c53b1a
font_01_sfnt_off0000dbcc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBCC 17548 bytes
SHA-256: 567a04608f09f12e8c1185b7fa7c81d8cfbf9f3b0d41e2f82ab80976dce258e2
font_02_sfnt_off0001093a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1093A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1