Malicious PDF — malware analysis report

Static analysis result for SHA-256 b864a85e6ca6770c…

MALICIOUS

PDF

85.6 KB Created: 2021-09-17 04:55:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 1b8bc0c8aee2595728471ff4ca46782e SHA-1: bb754aa0f0ea39be567e3ed2e6f6d0daeeb535e7 SHA-256: b864a85e6ca6770c337442c53019725f225446ec52f08f8e5e783ba052aec497
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded URLs, many of which point to disposable hosting or compromised WordPress sites, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the PDF structure itself is indicative of a malicious lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://pistant.ru/uplcv?utm_term=turn+off+my+android+phone+remotely PDF link annotation
    • https://powermailer.in/userfiles/file/nurusuva.pdfIn PDF document text
    • http://hugslock.com/app/webroot/img/files/61264852037.pdfIn PDF document text
    • http://studioscoponi.eu/userfiles/files/14166149584.pdfIn PDF document text
    • https://phr4u.com/files/15824825075.pdfIn PDF document text
    • https://listocrm.com/userfiles/files/79582227273.pdfIn PDF document text
    • http://mastervin.ru/files/file/vuzipedixetosiluga.pdfIn PDF document text
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/161407d8158801---21158178966.pdfIn PDF document text
    • http://klusjesindex.nl/images/uploads/nipev.pdfIn PDF document text
    • http://1carl.com/userfiles/file/7928819286.pdfIn PDF document text
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/1613548ea725e6---13460973389.pdfIn PDF document text
    • https://houstoncoinclub.org/FCKeditor/file/nekazer.pdfIn PDF document text
    • http://7sate.com/filespath/files/20210906041826.pdfIn PDF document text
    • http://rhondadejean.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/pakepanatakamamuwube.pdfIn PDF document text
    • http://interstyle.org/content/xuploadimages/file/taxivive.pdfIn PDF document text
    • http://amadpich.com/userfiles/file/12420022785.pdfIn PDF document text
    • http://www.tm-africa.com/beta/public/uploads/cms_filescms_files/99395671845.pdfIn PDF document text
    • https://playindiano1.in/ckfinder/userfiles/files/70436900461.pdfIn PDF document text
    • https://trsbarriersdirect.com/wp-content/plugins/super-forms/uploads/php/files/46otfva23pnfj6pvebtdnjrv2m/30819597432.pdfIn PDF document text
    • http://sspvjd.com/FileData/ckfinder/files/20210904_C539E770A75A41FE.pdfIn PDF document text
    • http://castel.lu/userfiles/files/xofuvitebitukilodifan.pdfIn PDF document text
    • http://fine-cottage.ru/userfiles/files/besokafisoj.pdfIn PDF document text
    • http://sklepjola.pl/userfiles/file/7115329389.pdfIn PDF document text
    • https://classconnbio.com/img-jacson/files/xilepisuwim.pdfIn PDF document text
    • https://www.tri-or.fr/tri-or/ckfinder/userfilesfiles/94737400493.pdfIn PDF document text
    • 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_off0000e9b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9B6 10772 bytes
SHA-256: f2681f21d25ae42a3b35584dd82f88705c5ea8fe4fd95408b73490ead5209a9a
font_01_sfnt_off0001024e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1024E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011a60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A60 17656 bytes
SHA-256: 4fb82bba9bac4ea86ae6532ff16ff0c98134a7c052b314350244e2fb4d00ab8f