Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8af79cf115acc20…

MALICIOUS

PDF

88.5 KB Created: 2021-07-04 13:06:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1fd58a1b56d0c98e3c7aa610994cab31 SHA-1: 3001d3477622f3a38b246641fe8614a39a50e354 SHA-256: b8af79cf115acc2086ab577ef66dbe811bafed026b9fa5c6e190f5df71ed26ce
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to websites hosted on compromised WordPress installations, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the embedded URLs are the primary indicators of compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://smidgel.ru/uplcv?utm_term=mosquito+larvae+in+dog+water
    • https://joyfool.art/wp-content/plugins/super-forms/uploads/php/files/0688c8751e5f89db6069a40bb5b4d757/69155095647.pdf
    • https://christembassyromford.org/wp-content/plugins/super-forms/uploads/php/files/d58a38c3a86eaf5d2639b4292e3d9a9f/98677628456.pdf
    • https://luxurytravel-show.com/wp-content/plugins/super-forms/uploads/php/files/f3d07b64878476e2c6f6eff5c7482c48/nusapaxujizejifabivaj.pdf
    • https://kantankacreative.com/wp-content/plugins/super-forms/uploads/php/files/2ec32f0fd9a6ab751ce4aafe846bdafa/rukelowopesokalujibut.pdf
    • https://flycam.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160a2f206341b0---mivavalowigox.pdf
    • https://fatheragneliti.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098805764403---fomixixawemoxutugevo.pdf
    • https://www.chortho.co.uk/wp-content/plugins/super-forms/uploads/php/files/q73ckk4l9u4tpir3ef05uldaus/77359390850.pdf
    • https://spencershaulageltd.co.uk/wp-content/plugins/super-forms/uploads/php/files/84574d4e2f28cbd397cdc9ebbd14c1f6/mumivilezuzofebupekedu.pdf
    • https://balance-global.com/wp-content/plugins/super-forms/uploads/php/files/88qpuqb35cmgflj7n3d606pftv/93842105741.pdf
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ac3fc04b6ab---lesifoze.pdf
    • http://tingyi-bnb.com/CKEdit/upload/files/tatetitenoli.pdf
    • https://pensiuneavlasin.ro/wp-content/plugins/super-forms/uploads/php/files/5773j8tjhlt4v2k9d6aennmmct/49231872567.pdf
    • https://alzubidi.com/userfiles/files/sulapit.pdf
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608fed33de7be---mojum.pdf
    • http://kangs78.com/clients/66216/File/pebixizibulorapeboforikan.pdf
    • https://ludifrance.fr/userfiles/file/35793882061.pdf
    • https://sellerflows.com/wp-content/plugins/super-forms/uploads/php/files/30d0bddbbd8244d2cde3a0027965b66e/suxeraze.pdf
    • http://ildungrice.com/fileupload/fckeditor/file/73149670279.pdf
    • http://raunlarose.us/wp-content/plugins/formcraft/file-upload/server/content/files/1606ce986f3645---56871751860.pdf
    • http://eraucheta.ru/uploads/file/zunexepuraxasinirosa.pdf
    • https://hophamthaibinh.com/upload/files/86225905039.pdf
    • http://sequirk.ie/userfiles/file/30617284089.pdf
    • http://donkaew-furniture.com/ckfinder/userfiles/files/viduvozekupamedurose.pdf
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160cc8fd4480f1---tiliwasusedawimer.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_off0000f6bc.bin
53ffedefdf60326a58e08afebfb3a50c4c2bea67478cc0a304be0221b50d594a
pdf-font-stream PDF embedded font (sfnt) at offset 0xF6BC 17348 bytes
font_01_sfnt_off00012411.bin
d5d8acb6e4f32635bb6f9862202d5e9a0a1d4197ec199ae051cf2e2506502b8e
pdf-font-stream PDF embedded font (sfnt) at offset 0x12411 10816 bytes
font_02_sfnt_off00013cb3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13CB3 16792 bytes