Malicious PDF — malware analysis report

Static analysis result for SHA-256 3199da832c55e0a0…

MALICIOUS

PDF

71.6 KB Created: 2021-09-30 16:41:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 165fef1c8e28610887af517b8bc9c1d5 SHA-1: 7a51222babbfef7f9aa10247c494a31f0f96ddc4 SHA-256: 3199da832c55e0a0105e4080fcb68c57d0f84ec8ebc350388e0febfcdd94edef
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV and an ML classifier as malicious. Heuristics indicate it functions as a link farm, hosting multiple PDF files on compromised WordPress upload storage. These links likely serve as redirects to malicious sites, a common tactic for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/161426fec037b1---datexalepaxado.pdf In PDF document text
    • http://www.vlaamspatientenplatform.be/_plugin/ckfinder/userfiles/files/25365635118.pdfIn PDF document text
    • http://geosond.pl/userfiles/file/28275702258.pdfIn PDF document text
    • http://www.hydro-tg.pro/upload/file/wuwusa.pdfIn PDF document text
    • http://weshare.vn/attachment/files/54974241944.pdfIn PDF document text
    • http://denis-lefebvre-services.com/fichiers/file/dobikobozeveduzorajejodud.pdfIn PDF document text
    • http://liceoadultos.juniorcollege.cl/userfiles/files/sowikovatozetudiven.pdfIn PDF document text
    • http://studiofranzoni.eu/userfiles/files/xuzubiwokexorexisive.pdfIn PDF document text
    • https://psg66.ru/admin/ckfinder/userfiles/files/puliruseges.pdfIn PDF document text
    • http://haphadoor.com/upload/files/botigu.pdfIn PDF document text
    • http://rybarict.cz/webpagebuilder/ckfinder/userfiles/files/pobipexupepulujapadapu.pdfIn PDF document text
    • http://archifolder.com/userfiles/files/wipoveduv.pdfIn PDF document text
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/16142ba0765c0a---gidaxobowogobarapot.pdfIn PDF document text
    • http://shardamedicalstore.com/singhania/downloads/file/fesarozigofiludosa.pdfIn PDF document text
    • http://shijijiaming.cn/filespath/files/20210904031209.pdfIn PDF document text
    • http://9y.bfage.com/upload/files/20210927011627.pdfIn PDF document text
    • http://pngroup.pl/ckfinder/userfiles/files/45561253755.pdfIn PDF document text
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/161406b637edee---17719986008.pdfIn PDF document text
    • http://xn--h49al33a2zdp0eo1x.com/DATA/file/20210918091323.pdfIn PDF document text
    • http://to-tuong.com/media/ckfinder/files/61541066348.pdfIn PDF document text
    • http://www.wallisandemmanuel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139680179b7d---regegoveniwowoje.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=ms+sql+androidPDF 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_off0000b242.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB242 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ca59.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA59 10152 bytes
SHA-256: b811f54bb4e01952334d87b9c42ddb0e94f05b89f133edcfa5324507a7d3f6e7
font_02_sfnt_off0000e0d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0D0 18708 bytes
SHA-256: 77638f1a44bc06180e6c5314e532b8b942f4f994453f2cc899726e6c8c4675a3