Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf21530f5cfc8f9d…

MALICIOUS

PDF

86.5 KB Created: 2021-07-16 16:10:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fab9e0a0bdeebd8330ccadcf98bd5199 SHA-1: 0facfdefc9166177925c634bcb13fba11c72c8ef SHA-256: bf21530f5cfc8f9d1771904cdea1c88cf4e28195369e5ca437463cce9050185d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a phishing or trojan threat. It contains numerous external links, many hosted on compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content or download sites. The presence of a 'download button' heuristic further supports the lure-based attack pattern.

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://pistant.ru/uplcv?utm_term=dead+poets+society+download+movie
    • http://sibmetiz.ru/upload_picture/8811410680.pdf
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/1c2on5qm47975pg5ue9hrjut8l/66091652719.pdf
    • https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/57i0cjjou6tloj76ilqjbjrph9/nowedixozu.pdf
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/1607af6deaa9a5---nonabesera.pdf
    • http://diysmart.net/userfiles/file/fegodelagudilo.pdf
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607a3d8a1aed8---19256078284.pdf
    • http://dom-nenilovo.ru/wp-content/plugins/super-forms/uploads/php/files/5533abfa9cb079625c6798898e1a8647/zewerikiwawon.pdf
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160986447e4547---lizuzefixatibajuvuwo.pdf
    • https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/8fgtqf0nft1fajd8d7nvp6j3jv/bonine.pdf
    • http://hysansam.com/fckeditor/userfiles/image/lufofimebixulaju.pdf
    • https://chiataiec.com/userfiles/Proj_Name//files/37087421545.pdf
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/lcr17r72mom5r31jp212cbvg63/39600658334.pdf
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/rnjqnrgmeapaepugsaugjint3i/20102967254.pdf
    • https://etimes.mn/uploads/files/babakipamad.pdf
    • http://xedaptap.net/userfiles/file/begezojigowumesepedova.pdf
    • https://la-klamm.org/userfiles/file/susujevekodomuramabudig.pdf
    • https://fellowpeo.com/wp-content/plugins/super-forms/uploads/php/files/768c23bc4a529927cde77a5489196c16/36008653289.pdf
    • https://noukos.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1609e7bbe1d192---45865027151.pdf
    • http://dzbnf.com/upload/file///mirazawojinorilevu.pdf
    • https://ratsimae.eemedia/contents/file/38926855022.pdf
    • https://laxmigrouppune.com/wp-content/plugins/super-forms/uploads/php/files/dbe23192966039ec9a7d9a49377c79b2/dagexijo.pdf
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/1608a98b831d3f---vapawokasemeked.pdf
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/ia7lp53p5ssdi7lr27822la7h1/13614326508.pdf
    • https://www.clubmanizales.com.co/wp-content/plugins/formcraft/file-upload/server/content/files/160c6b530641f1---tozegememujagubax.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_off0000ed13.bin
3a1417ef5d6a77a69968ff4b7ab8a8aa260945f9f5c8497fcd926eefb45abdbe
pdf-font-stream PDF embedded font (sfnt) at offset 0xED13 10844 bytes
font_01_sfnt_off00010628.bin
43b5d2db486ec92ff5c947c0f724a5f59507b22520ab103a585ea4b5e14ac0f1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10628 17092 bytes
font_02_sfnt_off000132a7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x132A7 16792 bytes