Malicious PDF — malware analysis report

Static analysis result for SHA-256 27f1cb43798b54c1…

MALICIOUS

PDF

89.7 KB Created: 2021-08-14 13:05:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: f60a8ac9988c3e3cb4a083efe4f7662b SHA-1: b0bd3a9031fe448266872bcb5f6ff505a6966b1a SHA-256: 27f1cb43798b54c1d9a65dd9b2f2589593955a5dca2380c7f86615aed906f5c3
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress sites, indicating a link farm or phishing campaign. The ClamAV detection and ML classifier strongly suggest malicious intent, likely to redirect users to malicious content or trick them into downloading further malware. No scripts were extracted, and the document body was unreadable, but the URL structure and heuristic firings are sufficient for this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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 https://svetpoznaniyaonline.ru/wp-content/plugins/super-forms/uploads/php/files/15282567b62f4e4c47932e1e45678155/78709308173.pdf In PDF document text
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/sm6eramkeok40r4877v3a5l0d5/lekuwuzabojiz.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160734196c7a68---33104801190.pdfIn PDF document text
    • http://patrick-vallot.com/upload/files/38683089827.pdfIn PDF document text
    • http://www.pilonidalsinus.gen.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160780fb817825---15119960351.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1608a4f9473460---sixalupubowusotuk.pdfIn PDF document text
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/37ce8407f23cd08db760854784bfd938/84446343002.pdfIn PDF document text
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160c56baeb6575---25558588710.pdfIn PDF document text
    • http://yjsyrj.com/userfiles/file/81519573675.pdfIn PDF document text
    • http://www.orhancoskun.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1cf270a69b---puwurugabuta.pdfIn PDF document text
    • https://excellencetogether.com/img/files/file/43049037978.pdfIn PDF document text
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/c1c9bb67a29e085bfbe34adfaba4f5a2/vusowaripuwakadekifuno.pdfIn PDF document text
    • https://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/51528f6515c7b56c5180a13ba14adfc1/sefosolanavasinewedowip.pdfIn PDF document text
    • http://waelfawzy.com/userfiles/file/fanofaf.pdfIn PDF document text
    • http://liubeauty.com/luutru/files/gukitelol.pdfIn PDF document text
    • https://festivalecolo.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609f6f0768ef8---15175584996.pdfIn PDF document text
    • http://bestofbeer.ru/ckfinder/userfiles/files/25634666382.pdfIn PDF document text
    • https://manorhair.com/uploads//files/202108072210528596.pdfIn PDF document text
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c7817ee5651---46658807847.pdfIn PDF document text
    • http://codienlanhminhquang.com/upload/files/6594020555.pdfIn PDF document text
    • https://implant-drill.com/userfiles/file/36542387845.pdfIn PDF document text
    • http://strategie-online.net/catalogue_dynamique/file/xidotoxep.pdfIn PDF document text
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608946bd1d28a---tekuluxi.pdfIn PDF document text
    • https://ideylia.fr/uploads/file/53232639652.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=cuanto+vinagre+de+manzana+debo+tomar+para+adelgazarPDF 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_off0000f889.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF889 17496 bytes
SHA-256: 430ca45cba05a496a27c4878063b0187d5319c160784e59f01bed4f8223227a3
font_01_sfnt_off000124a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124A2 10964 bytes
SHA-256: 9c9542893dc457a0e3a1b56962c1bf024ba1cca74e4b6b07028d51ad165aa482
font_02_sfnt_off00013db4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13DB4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1