Malicious PDF — malware analysis report

Static analysis result for SHA-256 87498c10eb0175bd…

MALICIOUS

PDF

81.6 KB Created: 2021-09-20 17:34:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8ca13f295feda4421c2bec4db9b9bb93 SHA-1: 915fbb66c3e704134a843363a61c58f149ac059d SHA-256: 87498c10eb0175bddbd4b1e98f39e2527f2da10f158f67feb19c3b41b5746148
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external links, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://gediklimakinahidrolik.com/resimler/files/76889720847.pdf
    • http://szkolaprywatnaleszno.pl/userfiles/file/tixixivofozova.pdf
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/hsupo88qftk1hss7a6mdtjptm2/mijolumibu.pdf
    • http://bbdecontra.com/userfiles/files/23028585413.pdf
    • http://saiprogetti.net/userfiles/files/tafunujetikebovev.pdf
    • https://www.vibrationmonitoring.asia/wp-content/plugins/formcraft/file-upload/server/content/files/161470a1b547ed---wivunuwetivu.pdf
    • https://birotex.rs/images/files/32921455500.pdf
    • http://tauroconsulting.pl/userfiles/file/53920552753.pdf
    • https://pinkrali.com/calisma2/files/uploads/36448742713.pdf
    • https://pustelnik-budownictwo.pl/ckfinder/userfiles/files/bufamifetujijafikalovu.pdf
    • http://tumakuruvoice.com/tumkurvoice/ckeditor/ckfinder/userfiles/files/23780408753.pdf
    • http://cesnek-vysocina.cz/UserFiles/File/nofewiguso.pdf
    • http://kommunikator.nu/demo/userfiles/file///bebegirumiparabufuzixus.pdf
    • https://www.alitec.es/js/ckfinder/userfiles/files/90454871402.pdf
    • http://csc0512.com/userfiles/file/20210917023710_72gy17.pdf
    • http://vladekoservis.ru/files/zasizakikobupixigapa.pdf
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614097ad962d1---76045040982.pdf
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/cic7kg1ldk46777iplcl99ssd6/pikepodogu.pdf
    • http://brcassociati.com/userfiles/files/zigopuwufudid.pdf
    • http://lirealestatelitigator.com/wp-content/plugins/super-forms/uploads/php/files/de89e8d68ff290cec4c20d86e2ad9ce1/worinosirugeretilo.pdf
    • http://gespk.com/userfiles/file/12483519255.pdf
    • http://24x7taazasamachar.com/assets/ckfinder/core/connector/php/uploads/files/95833366588.pdf
    • http://skoleniridicubrno.cz/ckfinder/userfiles/files/54666523772.pdf
    • http://pinturasoltra.com/images/slider/files/31461328524.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=list+some+collective+nouns
    • 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_off0000de9b.bin
7649502e2134a8c93b17f459f7da9d65787625566e02dc82c90874e59053459e
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE9B 16776 bytes
font_01_sfnt_off00010978.bin
060f9b3049e97ba718c08d4fb437d4d776a98645556c900c2db0228e718e430b
pdf-font-stream PDF embedded font (sfnt) at offset 0x10978 10252 bytes
font_02_sfnt_off0001208d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1208D 16792 bytes