Malicious PDF — malware analysis report

Static analysis result for SHA-256 78db58d4d741a179…

MALICIOUS

PDF

77.5 KB Created: 2021-09-12 10:22:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 9fe9baec3550ed5912b1398afbbef309 SHA-1: 10aa06d72d6beb0599fbe5a1be3154e65b562ed8 SHA-256: 78db58d4d741a1792061240e0fb73d69b2bd856ba3f2bf03dd83bfd4953df7e2
134 Risk Score

Malware Insights

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

The sample is a PDF file flagged by ML classifiers and ClamAV as malicious. It contains a high number of embedded links, many pointing to unknown domains, and a heuristic indicates a deceptive download button. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic suggests the document is part of a link farm designed to distribute malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://imagebuzz.net/ckfinder/userfiles/files/93942224937.pdf In PDF document text
    • http://osmed.cz/app/webroot/files/files/98988027324.pdfIn PDF document text
    • http://detaycopymatbaa.com/userfiles/file/xefavizapirebipifukogo.pdfIn PDF document text
    • http://yjeverspeed.com/userfiles/file/26908135071.pdfIn PDF document text
    • http://www.mbk-montage.nl/ckfinder/userfiles/files/sakenoratixos.pdfIn PDF document text
    • http://hkbroadwin.com/userfiles/kigabopazosozenido.pdfIn PDF document text
    • http://www.mustwalge.ee/data/content/files/54228637357.pdfIn PDF document text
    • http://gzcil.com/uploadfile/files/basotekijepiwesedo.pdfIn PDF document text
    • http://ashioke.com/images/library/File/desugubujuvozulolexew.pdfIn PDF document text
    • https://rtquery.reitoken.org/Coaching123/images/files/wokuwagabirefigef.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/161337f1677e7a---julozuniw.pdfIn PDF document text
    • https://icon-studios.com/userfiles/file/31297424650.pdfIn PDF document text
    • https://prestinieurope.com/userfiles/files/tipigu.pdfIn PDF document text
    • http://noithatdangcap.vn/app/webroot/uploads/files/29692116485.pdfIn PDF document text
    • https://www.casestilistas.es/ckfinder/userfiles/files/92201433404.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/161324f7123176---68424224898.pdfIn PDF document text
    • http://sciattella.net/images/file/53916304247.pdfIn PDF document text
    • http://rm-centr.ru/uploads/file/raxojekavifusomisewoxen.pdfIn PDF document text
    • https://ixiu-23.com/uploads/files/202109070602128289.pdfIn PDF document text
    • http://beautifulmoda.com/userfiles/files/79928669603.pdfIn PDF document text
    • http://babijie.com/upload_fck/file/2021-9-2/20210902142831688053.pdfIn PDF document text
    • https://aquafilling.com/userfiles/file/rowowadov.pdfIn PDF document text
    • http://montpellier-business-plan.fr/mbp/upload/images/images/upload/ckfinder/zexodaxudo.pdfIn PDF document text
    • http://nenorm.com/files/files/jaxununobeto.pdfIn PDF document text
    • http://purplebyanki-com.bvirani.com/ckfinder/userfiles/files/60816558262.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=gta+v+obb+file+download+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_off0000cc63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC63 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e47a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE47A 10512 bytes
SHA-256: 25599ba95d6491366ba5c6048010d2f575dd397f950acd8233e1b29d1b33d6f4
font_02_sfnt_off0000fc92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC92 16936 bytes
SHA-256: a1d173b8f95000eb91edbf49e6a7bedeb3d5a6f297799c26a514d439e855d332