Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f8be4d0c2162c72…

MALICIOUS

PDF

96.9 KB Created: 2021-09-01 23:57:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: dee9c3c988b593af7c9c892fd0b3152b SHA-1: b02dd833bdf78100f762eb24d1d03585f5324612 SHA-256: 5f8be4d0c2162c72f086558666c0ba1700cc75a2d49044a438af87413bd0db7c
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, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of a link farm on disposable hosting and the use of UTM parameters in one URL further support a phishing or malicious distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://scales-center.com/shop/fck_file/file/68634041170.pdf
    • http://baruraprotidin.com/assets/ckfinder/core/connector/php/uploads/files/91931649006.pdf
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/fkme44ph6rmg4fcigb5rtk4969/29619415319.pdf
    • http://thm-holding.ru/wp-content/plugins/super-forms/uploads/php/files/50d4deb0debdc1f664f57f77bb51d7e0/bemuzejemetemisadab.pdf
    • https://taechoclub.com/FileData/ckfinder/files/20210818_AAC71A1231954A89.pdf
    • http://mgbig.com/upload_fck/file/2021-9-1/20210901030240288919.pdf
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/1612a3e23e532e---gefof.pdf
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160dee0df0df74---zujowutidexuxojosuga.pdf
    • https://californiaoptionsrealestate.com/wp-content/plugins/super-forms/uploads/php/files/3a4b4839d974f54a6161d86ddae95c57/48889631625.pdf
    • http://schouteninterieurwerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16072e1b68a8bf---kemosot.pdf
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3aad629e4d---30331590724.pdf
    • https://willmarlakesarea2040.com/ckfinder/userfiles/files/lojavazif.pdf
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609631ecf0f96---regawawusezi.pdf
    • http://trungnguyenjsc.vn/uploads/image/files/65157117065.pdf
    • http://aelma.com/sites/default/userfiles/file/72335033620.pdf
    • https://shinyjewellers.com/wp-content/plugins/super-forms/uploads/php/files/p63np8gtj8hbg25adfm3but36v/guwugazinejobobomumozuj.pdf
    • https://satesayap.com/contents/files/45976346579.pdf
    • https://spherule.org/wp-content/plugins/super-forms/uploads/php/files/6785dfecf7e81ad0bb43bfa5d315f438/45978394735.pdf
    • http://111-orte.com/testarea/cwsCMSlight/media/files/vewejizi.pdf
    • https://petala.gr/userfiles/file/97203917669.pdf
    • https://tramhuonghanoi.vn/upload/files/72960701692.pdf
    • https://georgiamusicpartners.org/wp-content/plugins/super-forms/uploads/php/files/42067abe661a38411d011fc232c6f821/36816266285.pdf
    • https://aprilboya.com/userfiles/file/jivow.pdf
    • https://veritiesinstitute.com/wp-content/plugins/super-forms/uploads/php/files/0b503ca8c8b1528ddb48e8c7de8ed162/jusuta.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=the+fifty+shades+of+darker+full+movie
    • 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_off000110a0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x110A0 16792 bytes
font_01_sfnt_off000128b2.bin
d2d6f619272134490f6a4828e1b41cdbbfd876233ca28c63c3bc6b82d8a6ed3a
pdf-font-stream PDF embedded font (sfnt) at offset 0x128B2 19524 bytes
font_02_sfnt_off00015beb.bin
a417ec5341b904038c2005ddb70798e4a0d2ede5a012c992e6449d922d9ebdeb
pdf-font-stream PDF embedded font (sfnt) at offset 0x15BEB 10848 bytes