Malicious PDF — malware analysis report

Static analysis result for SHA-256 7c1c83e5304dd6b4…

MALICIOUS

PDF

81.6 KB Created: 2021-09-18 04:54:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: da48abbf382cd73b39b378ad0c56a84b SHA-1: 291da0d3720cc84945542d6fc359211f309375f8 SHA-256: 7c1c83e5304dd6b497365df9b88e33cc3daf01e9ac2f56d9ee8f6276ade5f159
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and link farm behavior are consistent with techniques used to deliver second-stage payloads.

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://garglob.ru/uplcv?utm_term=bluetooth+lag+android PDF link annotation
    • http://wakesup.org/userfiles/file/68161081989.pdfIn PDF document text
    • http://turhantur.com/turhantur/files/37909183289.pdfIn PDF document text
    • http://internet-trade.eu/UserFiles/file/63721614247.pdfIn PDF document text
    • https://jss-moms.si/upload/File/nokelazikotodufimilik.pdfIn PDF document text
    • http://honda-vo.com/upload/file/kotazakulewigaxijilodupem.pdfIn PDF document text
    • http://cosmosimpex.com/app/webroot/ckfinder/userfiles/files/saruratixejisekavanep.pdfIn PDF document text
    • http://chickendaylacrescenta.com/uploads/files/xuzunebopadad.pdfIn PDF document text
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16139bb42a8a13---pafivevinakijomabupewe.pdfIn PDF document text
    • http://rowerowaszkola.pl/imgturysta/files/sutubukuke.pdfIn PDF document text
    • http://studiocinti.eu/userfiles/files/19211269883.pdfIn PDF document text
    • https://hr-serdahel.hu/images/file/bafexufubawusapisajor.pdfIn PDF document text
    • https://rakowka.pl/userfiles/file/toxururaj.pdfIn PDF document text
    • http://wideanglepackaging.com/ckfinder/userfiles/files/kedin.pdfIn PDF document text
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613146ecee163---dikiron.pdfIn PDF document text
    • https://eghamatkade.com/basefile/eghamatkadecom/files/6706663759.pdfIn PDF document text
    • https://cleanenergy.mn/uploads/files/98201779953.pdfIn PDF document text
    • http://mextro.de/upload/files/31042449042.pdfIn PDF document text
    • http://goldenstarhotel.vn/images/uploads/files/17263765732.pdfIn PDF document text
    • https://matao.ro/app/webroot/files/userfiles/files/wixanegojezef.pdfIn PDF document text
    • http://gomsuhoangminh.com/app/webroot/uploads/files/36966528615.pdfIn PDF document text
    • http://techscreening.com/userfiles/files/99947033246.pdfIn PDF document text
    • https://ntc-container.com/upload/files/81736684928.pdfIn PDF document text
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613357e35bba3---24633368117.pdfIn PDF document text
    • https://sushixusa.com/userfiles/files/81750913414.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_off0000d746.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD746 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ef58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF58 19008 bytes
SHA-256: 4e2430e823266edf3fffc6524620a602db7af3aa0db38943757d22091a4e60a9
font_02_sfnt_off000120e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120E0 10512 bytes
SHA-256: 98087b8a77a09390e46b466401d41258715fc97262470c0a742cad59604e3d76