Malicious PDF — malware analysis report

Static analysis result for SHA-256 77a3e41132f6efa9…

MALICIOUS

PDF

90.1 KB Created: 2021-06-29 11:05:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: dde017e21ff87c648829623148d72f1d SHA-1: d5d372e44256cde4038764a3b7b9d0415a66b167 SHA-256: 77a3e41132f6efa9aafbd9683dd902f8a71b003cd98e3797bb012a40f3c1507d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous external URIs and link farm heuristics, indicating its primary purpose is to redirect users to potentially malicious websites. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the structure and embedded URLs are indicative of a malicious PDF designed to lure users to external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 7

  • 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.
  • 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://synerhu.ru/uplcv?utm_term=cucet+msc+physics+previous+question+papers
    • http://robbes.nl/media/files/rimamajeroguzurepunim.pdf
    • https://oklogistic.lv/upload/file/firiwadisoda.pdf
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607043301a1b4---begukepenoxuxo.pdf
    • https://fonixkoncert.hu/upload/file/semosepixuberepox.pdf
    • https://staffxrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/8536b44c8e219658d1ccefe532b04b5d/23363036476.pdf
    • https://atkarisuli.hu/userfiles/file/22260710430.pdf
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b91adc82d0e---55612221113.pdf
    • https://travelstore.tn/userfiles/file/48103846987.pdf
    • http://sentezetutmerkezi.com/upload/ckfinder/files/diboduvepagezufi.pdf
    • https://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/d333511c8874aeebc818c085fb404c00/47733507292.pdf
    • https://expresstestingatl.com/wp-content/plugins/super-forms/uploads/php/files/fe8760044efcf81d10d7baf8ffdc85e6/zagamogelavodajen.pdf
    • https://rjiminfra.com/wp-content/plugins/super-forms/uploads/php/files/1d2accf4d532830373667f5da1953af2/fozipapovapipebugelejoti.pdf
    • https://laneopx.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b3c9c6d9727---derizigorimumajonovirum.pdf
    • http://alphabodysupplements.com/newerac2c/userfiles/file/ximute.pdf
    • https://tripleccompanies.com/wp-content/plugins/super-forms/uploads/php/files/44b0df245d5c0e543144dfc0953dadf0/delegode.pdf
    • https://playgametoday.ru/wp-content/plugins/super-forms/uploads/php/files/ef8bace629ac58be2b5c1bd97eaeab7b/nufuziwijas.pdf
    • http://sun-eko.eu/files/file/94305595221.pdf
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/289bd7a76039a24d16373f16c363b411/60249537625.pdf
    • http://kochamsushi.pl/UserFiles/file/28963812460.pdf
    • http://ruihuitax.com/files/file/dixuguzutevuz.pdf
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071b2b4b9ba3---ledemerikosagid.pdf
    • http://bioscipublisher.com/files/upfiles/file/14060729487.pdf
    • http://bioident.pl/photos_fck/file/juwuzulire.pdf
    • http://schodylux.pl/userfiles/file/tidenanuxinuvanef.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000facf.bin
712ee3857dc56f9ccb1235017b2b2bd274a0c426cad7077186e5e1b90f50c322
pdf-font-stream PDF embedded font (sfnt) at offset 0xFACF 11048 bytes
font_01_sfnt_off00011473.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11473 16792 bytes
font_02_sfnt_off00012c85.bin
ee1175c202dd989c4e0b29b3d064c54d958a04880fce7a6f8ea28b498d7bd7e6
pdf-font-stream PDF embedded font (sfnt) at offset 0x12C85 17068 bytes