Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ced7bcb9853c502…

MALICIOUS

PDF

89.6 KB Created: 2021-09-07 11:46:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 91cae49c9b30c5125c2bf8be39bf8f30 SHA-1: d79470fe2a0e1e8e3d82faeb033b10d9bd3add92 SHA-256: 4ced7bcb9853c502819e84c76cfc4cff0dd8951c21ef47f831a79c17df24d085
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF contains embedded JavaScript, a common technique for exploiting PDF vulnerabilities or redirecting users. The presence of multiple links pointing to compromised CMS upload directories and disposable hosting suggests a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly indicate malicious intent, likely involving the execution of embedded scripts to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9967

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 https://utilitydiscount.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b82f77c20c1---wadekufuxiwapadagujonebu.pdf In PDF document text
    • http://businesslegalgroup.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/83644815094.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613436567ba8b---29046509248.pdfIn PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608eb3d916e83---joporamopobipujinovutu.pdfIn PDF document text
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/5b877dad097098bd631461fbb9e1cb73/47496986226.pdfIn PDF document text
    • http://flirtproducties.nl/ckfinder/userfiles/files/70892584795.pdfIn PDF document text
    • http://minhnguyenvn.com/uploads/userfiles/file/55534467840.pdfIn PDF document text
    • https://strategieb2b.ca/userfiles/file/56761070679.pdfIn PDF document text
    • http://www.agrosystem.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160a8132f92538---12366195679.pdfIn PDF document text
    • http://motorlustor.net/userfiles/file/8515138903.pdfIn PDF document text
    • https://ozsersogutma.com/upload/files/5802701994.pdfIn PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16089ff4e3595c---12455798117.pdfIn PDF document text
    • https://ktmcollege.org/public_html/userfiles/file/92642471762.pdfIn PDF document text
    • http://voijin.com/userfiles/files/munuguluwalaxubumuseza.pdfIn PDF document text
    • https://kheops-so.fr/ckfinder/userfiles/files/wenafi.pdfIn PDF document text
    • https://mziagroup.com/wp-content/plugins/super-forms/uploads/php/files/ueradlkk92qb3ve138c0hmd2r0/jopemepuj.pdfIn PDF document text
    • http://kaizousha.com/js/upload/files/bovegoribenifavijonis.pdfIn PDF document text
    • http://anvlaw.com/userfiles/file/49544624398.pdfIn PDF document text
    • http://adabaskimerkezi.com/upload/file/9326433068.pdfIn PDF document text
    • http://anjilh.com/uploadfile/file///2021043010541963.pdfIn PDF document text
    • https://giraffeng.net/infodaily/gen-ckfinder/userfiles/files/zarolubuzekivutiwenu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=world+environmental+issues+pdfPDF link annotation
    • 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_off000100d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100D0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000118e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118E7 10820 bytes
SHA-256: c06896cdd6d2f5916b6f3ea094ee84a0d20eb6c881206330d0a5d5bed9edb058
font_02_sfnt_off000131da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131DA 18060 bytes
SHA-256: 95a988020a6f418ef8e03df38a7132023c92fc5bbc94de5e7b1d5f0e31e5f70e