Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f414ca4b0c82aa8…

MALICIOUS

PDF

88.1 KB Created: 2021-07-16 12:21:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 91a64bafbc58f0fb27b9ede45586f24c SHA-1: d919ab03f2c70ac8439fa1f12f729ae8327be874 SHA-256: 8f414ca4b0c82aa85e683f0f6e17935a83d9ffa2f24df0b6d9ab8b1a92611f22
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics indicate the document functions as a link farm, directing users to multiple external URLs hosted on compromised WordPress sites and other disposable domains. While no scripts were explicitly extracted, the nature of PDF link farms often involves JavaScript for redirection or obfuscation, suggesting an attempt to deliver a second-stage payload or conduct phishing.

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 http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1606f2082b4f58---54471592809.pdf In PDF document text
    • https://aftaplan.com/works/peepsparty/html/upload_files/file/kefadixonafakevov.pdfIn PDF document text
    • http://meyanko.com/userfiles/file///rijejawe.pdfIn PDF document text
    • http://www.maarsehoveniers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c76e0fc4a67---jumirata.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/4d50lsdnie39df03hlcmeuf2b1/gezasuritilofozewogagimob.pdfIn PDF document text
    • http://changrung.com/ckfinder/userfiles/files/8341932948.pdfIn PDF document text
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b9cbb25cf89---sawofodomike.pdfIn PDF document text
    • https://angelsstaff.com/uploads/file/83462443287.pdfIn PDF document text
    • http://nfc.soo.jp/file/61301959662.pdfIn PDF document text
    • http://hopkinshigh62.com/clients/7/77/7764523e397120ad9b09b1da26998858/File/98159038513.pdfIn PDF document text
    • http://cosyromania.com/media/file/guxetu.pdfIn PDF document text
    • http://charivne.info/images/file/lopafenodoragirol.pdfIn PDF document text
    • https://ifacemount.com/wp-content/plugins/super-forms/uploads/php/files/va748h3fej1qk3f8su40c4uhon/7098288601.pdfIn PDF document text
    • https://bayardplaza.co.uk/wp-content/plugins/super-forms/uploads/php/files/t35dqeu0nkekrdq37t488ksnpk/89510309271.pdfIn PDF document text
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6550df050f---99541505929.pdfIn PDF document text
    • https://transcendenceit.com/wp-content/plugins/super-forms/uploads/php/files/7989bf5ee4c605a8bdab997d33ca14d0/rowajipudisax.pdfIn PDF document text
    • http://www.urbanwaterways.info/files/76658747544.pdfIn PDF document text
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/fdaa91bd90cb1a082fe6a3ca1000a7a9/51289144861.pdfIn PDF document text
    • https://eyestech.in/wp-content/plugins/super-forms/uploads/php/files/bpfrjq1od7r5990si379otlsvg/1097562979.pdfIn PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160bdebc6cfbad---mofisazugiwizobikak.pdfIn PDF document text
    • https://hmjrgoldhockey.org/wp-content/plugins/super-forms/uploads/php/files/48f5d0e87493d8ee7ff82d75dfd71468/25666293447.pdfIn PDF document text
    • https://nikken-engineer.jp/export/sd205/www/jp/r/e/gmoserver/8/6/sd0748886/nikken-engineer.jp/fckeditor/upload/file/41659087036.pdfIn PDF document text
    • https://lcd96.ru/wp-content/plugins/super-forms/uploads/php/files/9da776069be9c19cbadac403387c1e66/33635741157.pdfIn PDF document text
    • http://juniorsmagazine.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075279255169---maxibugofinapusokinod.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=class+9+english+in+the+kingdom+of+fools+questions+and+answersPDF 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_off0000f4a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4A0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010cb2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CB2 16888 bytes
SHA-256: fa33fbbdbddc6a2361d89830700e57b5b1e885f723c6676b6a2ff2a08367a32b
font_02_sfnt_off00013866.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13866 11424 bytes
SHA-256: 4507f87304c639002dcc95639658d3a498b055732ad74d6fc516193feb824da4