Malicious PDF — malware analysis report

Static analysis result for SHA-256 b561a165f1a57ad1…

MALICIOUS

PDF

79.9 KB Created: 2021-09-16 04:51:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: e6bf40e0e98b3fa715049c7c97431c3a SHA-1: f539aeaf75b064c48917f651340c66153fd6cbeb SHA-256: b561a165f1a57ad148fd254f632a8b89ed99d67cf26520e29f33f10982f50b80
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. It contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The presence of these links suggests an attempt to lure users to external sites for malicious purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 http://hosteleriayvending.com/ckfinder/userfiles/files/88001677727.pdf In PDF document text
    • http://indianapit.thriftstorewebsites.net/flash/indianapit.thriftstorewebsites.net/file/56152844261.pdfIn PDF document text
    • http://bulmarconsult.com/files/pamajugojenamuvetapiwagi.pdfIn PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/0adf780345721a6bf598985290518a23/69027426363.pdfIn PDF document text
    • http://zrdb-drogbud.pl/Upload/file/gimebigepuninadexa.pdfIn PDF document text
    • http://matchonusa.com/uploads/files/jikuse.pdfIn PDF document text
    • https://costarica4d.com/contents/files/18886671050.pdfIn PDF document text
    • https://spencershaulageltd.co.uk/wp-content/plugins/super-forms/uploads/php/files/e341f198104b2da7057eff59d11ab0d2/87649926336.pdfIn PDF document text
    • https://tebra.si/userfiles/file/karurubidoxuwo.pdfIn PDF document text
    • https://daiichitravel.com/uploads/news_file/39320377983.pdfIn PDF document text
    • http://savages.lu/imagesRTE/files/52879864619.pdfIn PDF document text
    • https://aristi-trap.com/upload/users/files/sumazurug.pdfIn PDF document text
    • http://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b16448934d---wazorosuwomilix.pdfIn PDF document text
    • https://archielectronics.com/userfiles/files/rebotigubasararusazad.pdfIn PDF document text
    • https://homeuu.biz/upload/ckeditor/pages/files/likenumeruwoloxemijufoxe.pdfIn PDF document text
    • http://staropolski.net/Upload/file/wakovoxoli.pdfIn PDF document text
    • http://vetsnab32.ru/userfiles/file/62039428648.pdfIn PDF document text
    • http://xn--80akazwaeiw.xn--p1ai/editorfiles/file/nibiberigegelakitajujidal.pdfIn PDF document text
    • http://highgaincomposites.com/img/file/202191305044.pdfIn PDF document text
    • http://lammermoor.net/imagenes/file/rilesumovefabuwadetadif.pdfIn PDF document text
    • https://weborder.cloud/userfiles/file///lusovamakosutedisusewedo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=quick+hookup+sites+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_off0000d3fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3FC 17976 bytes
SHA-256: b60f7e0b4abf236c2a942aaa25fb2fe8c9b9bd3cbd4055c6f9e94fa18d7b3426
font_01_sfnt_off00010280.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10280 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011a97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A97 10516 bytes
SHA-256: 75fe1b45dc13895343d427e5fcb8e74e0dd58497ccc004545906f4530f0d586c