Malicious PDF — malware analysis report

Static analysis result for SHA-256 33459c6907a0510e…

MALICIOUS

PDF

80.6 KB Created: 2021-09-16 21:44:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: dfcf537c45c32a5ae9ec900c63e98556 SHA-1: f173a0c870a7ebae4bae40db716d306598fe3b76 SHA-256: 33459c6907a0510e5da318fac413a33777946876a40962b3b444bf9b3ee0e8fb
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the document functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS upload storage. The presence of numerous unknown URLs suggests an attempt to distribute further malicious content or phish for credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://medicaldistri.com/ckfinder_files/files/99601273359.pdf In PDF document text
    • http://kronikarp.pl/ckfinder/userfiles/files/47529645010.pdfIn PDF document text
    • http://agro-vostok.ru/userfiles/file/kaxafifitokifot.pdfIn PDF document text
    • http://bangdinhphucat.com/quangbasanpham/app/webroot/upload/image/files/59803786199.pdfIn PDF document text
    • http://aurastaffing.es/upload/file/60182758439.pdfIn PDF document text
    • http://coreaad.com/DreamDataUpload/file/93534276184.pdfIn PDF document text
    • http://wsm.hk/images/files/guvexuriwekiguj.pdfIn PDF document text
    • https://fundacionamigosdelmarcaribe.ong/ckfinder/userfiles/files/tabeta.pdfIn PDF document text
    • https://rebates.forex/wp-content/plugins/super-forms/uploads/php/files/vtfhjvt1hj01mdk2pvpi1l5n57/58650010733.pdfIn PDF document text
    • http://fitsiluet.cz/data/file/zusovoliwaxabir.pdfIn PDF document text
    • http://yacpa.org/yacpafiles/file/siwolosuk.pdfIn PDF document text
    • https://telliogluhukuk.com/userfiles/file/36448084217.pdfIn PDF document text
    • http://dioceseofniranam.org/userfiles/file/45132025581.pdfIn PDF document text
    • http://tecs4.com/intranet/ckfinder/userfiles/files/birajujusifitekupemumuw.pdfIn PDF document text
    • https://weldingportal.it/userfiles/file/pegapudivewujelugu.pdfIn PDF document text
    • http://apsons.eu/files/file/78494211335.pdfIn PDF document text
    • http://www.champcaregivers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143365a6bd99---34990854180.pdfIn PDF document text
    • http://tiquital.com/documentos/file/81605905940.pdfIn PDF document text
    • http://nissanotogovap.com/uploads/images/files/solesewogegiditapude.pdfIn PDF document text
    • https://premiumvipbusiness.com/wp-content/plugins/super-forms/uploads/php/files/97c8048e849d486347f774c898d0dee2/90229849563.pdfIn PDF document text
    • http://abaj.cz/UserFiles/File/89733795989.pdfIn PDF document text
    • http://ricarda-allegra.de/userfiles/file/mavimanezoturo.pdfIn PDF document text
    • http://phuongdonggolf.vn/app/webroot/uploads/files/24916996281.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=how+to+hack+into+someones+instagram+for+freePDF 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_off0000d479.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD479 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ec90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC90 10908 bytes
SHA-256: 49e6a4731fe775232ccbe205a704abbb593d2fe8c027677fdd42018ced137de8
font_02_sfnt_off000105ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105AC 18452 bytes
SHA-256: 35197cf71c1d3df1d00ecd831a14a2c3906ef4f8046485b42463add68ef72a95