Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4e10a4d55cdb0a0…

MALICIOUS

PDF

119.9 KB Created: 2021-07-15 17:59:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 984228a92ca7e8da9e8dd1893091e880 SHA-1: 585815b72c471da494b28d8705b8c40d30681734 SHA-256: b4e10a4d55cdb0a0e2e5382af0e49fe4bd67d7d03118067a1292d32ff9e73b99
156 Risk Score

Malware Insights

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

The PDF file contains a link farm pointing to numerous URLs, many of which are hosted on compromised WordPress sites. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. The presence of multiple links on disposable hosting and the use of 'utm_term' parameters suggest an attempt to obscure the true destination and evade detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

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 http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/n2soh8b18l0urjgm1heuan0lp0/66676779398.pdf
    • http://nakatka.com/files/file/dulagewukexuxo.pdf
    • https://michaels-limo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f030b71fe31---xurajufinunuromiguxije.pdf
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/da952c259825986f2b8af81e31f8918c/jazironizaxejafavotobob.pdf
    • https://westcoastmovers.ca/wp-content/plugins/super-forms/uploads/php/files/ff6e4ld4nfdkn0nkk3mg7qpro4/tesupi.pdf
    • https://torrentclub.vip/wp-content/plugins/super-forms/uploads/php/files/9r9nct4gt23uqd48b37feaakl8/nowajipozigawukig.pdf
    • https://grancom.by/upload/docs/rupasoganinamodobunuj.pdf
    • https://majorsagilekvaros.hu/uploads/file/34829673608.pdf
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/160cd784916824---zesejularamumupisasum.pdf
    • http://www.rkcomdesignservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075a324f343e---gufakogasopizalo.pdf
    • https://www.drserapkagan.com/wp-content/plugins/super-forms/uploads/php/files/emlfkg1ebelescr2ouq0vpaov7/zelonavo.pdf
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a90551859b4---japilo.pdf
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1b7757995b---vobozeduvo.pdf
    • https://www.ideaklinikankara.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c87ab8828b---75709995222.pdf
    • http://blatt-gruen.ch/files/91393580987.pdf
    • http://concept-art.nl/app/webroot/files/userfiles/files/9922366768.pdf
    • https://xn----9sbccjdbca7cyaieg1a3j.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/7466123af3daae3f6193da13b3772954/jozepugosofidowozam.pdf
    • http://3e-recycling.ru/app/webroot/filesfiles/wireruvoketedumoxoji.pdf
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608020b16e65e---jexavapoxufulexopebafexan.pdf
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/c221b89bf8696056898a4ee27dcecc08/50373947633.pdf
    • https://floridaholidayplanner.com/wp-content/plugins/super-forms/uploads/php/files/d3aa0db9f6ea7bb71787e2112f053613/webesadita.pdf
    • https://vandolderskb.com/images/usr/10778232083.pdf
    • http://stroi-sistema.ru/img/jotiziwobozixedi.pdf
    • http://alacarte-design.de/userfiles/file/tukokifobuzusokomonijon.pdf
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160dfb6e0671f6---zulesudoxituguxe.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=linked+list+in+c
    • 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_off0001744c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1744C 16792 bytes
font_01_sfnt_off00018c63.bin
1cb475114060a3ce21af59c4fb77687d30a7d1b96c83d6ebe9cf74f6cd181c7c
pdf-font-stream PDF embedded font (sfnt) at offset 0x18C63 10032 bytes
font_02_sfnt_off0001a2ba.bin
60e0ea8a76eeebaa78a5b1b905cac672d2292c205a1fe3a8fb00b832c4788212
pdf-font-stream PDF embedded font (sfnt) at offset 0x1A2BA 18288 bytes