Malicious PDF — malware analysis report

Static analysis result for SHA-256 66f7315ca1deb4b9…

MALICIOUS

PDF

86.6 KB Created: 2021-06-26 16:00:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b5c1e532ba0025f7145f71e48fdb3ad6 SHA-1: 6a307b072dc58ff2b0b00006e19cdcd6012930d1 SHA-256: 66f7315ca1deb4b9d863896b1da1f80382850012eb9173553433c62636bd33da
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories, suggesting it functions as a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of UTM parameters in some URLs further supports a campaign-driven distribution method.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://philabc.ru/uplcv?utm_term=chapter+2+ts+grewal+class+12+solutions
    • http://coimbra.hu/uploads/ckfinder/userfiles/files/63374760563.pdf
    • https://cedarcreeksauce.com/wp-content/plugins/super-forms/uploads/php/files/6c5cf6adf178e3fb7fcf2dffa185e771/54130739894.pdf
    • http://utopiasacramento.org/clients/0/07/071cdeedc048305be324eb10ab8031d4/File/85230057927.pdf
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c978108b4c0---zumewupuwesirugajepure.pdf
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/pvdfjkp0mrvqce9sm439mj33mf/68305475874.pdf
    • https://www.rydalmereprestige.com.au/wp-content/plugins/super-forms/uploads/php/files/3l7hrs4mvp92r4feq0p6559ruo/lowowosafuku.pdf
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/7fef6081973e18a57452eea8d5ff7a6b/vejebumawetedevijadanagen.pdf
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/160a31198d4a61---getekel.pdf
    • https://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/31a17777f5df4131bb3bbe0a9c47423f/74677737053.pdf
    • https://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/012f16af8ffb44df79e5ab0f00302884/tobonixowexim.pdf
    • https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/qbb9nfp193du3t8qvjnkpo30lu/50482543708.pdf
    • http://mlight.cz/archiv/file/xuzurojizunumikotoju.pdf
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/0d44582cead743000307f00abfd9b88b/90205362576.pdf
    • https://kingyao.com/uploadfiles/files/20210613_065635_7135.pdf
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608df0a98fc84---vabunosolitekabasuwaf.pdf
    • http://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607bdf81ce1c9---68056418449.pdf
    • https://dadrarad.ro/userfiles/file/52621294270.pdf
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/160b3e75ce2ba1---64983304678.pdf
    • https://mangonebike.com/uploads/file/94267264150.pdf
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/160a1c7af73140---12340029878.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074344157e05---20736681751.pdf
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/44e15159a0e96bcf3763adec7c19ee61/15580671370.pdf
    • https://www.helpagesl.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a85ce00a64c---29236394961.pdf
    • http://studiosimonepantaleo.it/userfiles/files/79006628376.pdf
    • http://hugslock.com/app/webroot/img/files/44287695215.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_off0000eef3.bin
b745640e5e723e0ee80169e41945fa4576abe8593e6d969006a3a34372f69346
pdf-font-stream PDF embedded font (sfnt) at offset 0xEEF3 11044 bytes
font_01_sfnt_off000108d7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x108D7 16792 bytes
font_02_sfnt_off000120e9.bin
502c85365fb64dc6b16930dd3aa9d1ae24948ed60ade0615b88d55493994ecf3
pdf-font-stream PDF embedded font (sfnt) at offset 0x120E9 16936 bytes