Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c7a3ff8052d199f…

MALICIOUS

PDF

81.6 KB Created: 2021-09-07 15:07:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 8f39fa604709400c45c58974a6fd7e3f SHA-1: 2d331a9ce5116cbd1fe49084de746132c908e413 SHA-256: 8c7a3ff8052d199f8fa3e58ef8f18f6e4ed220a8d02c21ea3c07a47bb2db70eb
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous embedded URLs, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and unreadable, providing no further context on its specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://www.schroedersales.com/wp-content/plugins/super-forms/uploads/php/files/bc2bf5b51af9fd588f3de9399cafe622/73934179838.pdf In PDF document text
    • http://metalltechnik-kutschi.at/dafoxedu.pdfIn PDF document text
    • http://agavietnam.com/img/files/62778553815.pdfIn PDF document text
    • http://humidorio.de/ckfinder/userfiles/files/gepamatabon.pdfIn PDF document text
    • http://wallawallahighschool1968.org/clients/75819/File/jogabuga.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1608aa5d7a7e1a---27998694850.pdfIn PDF document text
    • https://rebates.forex/wp-content/plugins/super-forms/uploads/php/files/9vi40vbg29332he4igj2779lp4/nupajuxebuzipobiv.pdfIn PDF document text
    • https://rozgarnetwork.com/ckfinder/userfiles/files/fuzujenafabunanig.pdfIn PDF document text
    • http://darstin.com/userfiles/files/15302870923.pdfIn PDF document text
    • https://bustotoronto.com/userfiles/file/22014667026.pdfIn PDF document text
    • http://liqaa-lb.com/files/userfiles/files/mudimuzotap.pdfIn PDF document text
    • http://stigstudiotecnico.it/userfiles/files/11529652633.pdfIn PDF document text
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088bff19b1a4---83640505553.pdfIn PDF document text
    • http://engroupe.ca/aym_image/files/dubarexuna.pdfIn PDF document text
    • https://neoville.ru/wp-content/plugins/super-forms/uploads/php/files/c93413cd5647347b5b447645fd3269e1/70903965422.pdfIn PDF document text
    • http://kyanite.tv/userfiles/file/menuvesuvagowamipeke.pdfIn PDF document text
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160b0844b1e806---redajulitibedenexag.pdfIn PDF document text
    • http://ebsenglish.net/_UploadFile/Images/file/doser.pdfIn PDF document text
    • https://www.cr-sdc.org/wp-content/plugins/super-forms/uploads/php/files/6cc6e6d113388c78bd90a55be57c0989/kuzuw.pdfIn PDF document text
    • https://newtech-utm.pl/userfiles/file/zifinadiruja.pdfIn PDF document text
    • http://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/1743958fa59eabd7b3683c195a4699e0/jifelade.pdfIn PDF document text
    • http://beerskiboot.com/img/upload/file/7165449409.pdfIn PDF document text
    • http://longarmquiltacademy.net/fckeditor/userfiles/file/71693004927.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=infosys+interview+questions+and+answers+for+freshers+pdfPDF 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_off0000d8d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8D1 18000 bytes
SHA-256: 16b394fc7b7f5d76dfa08f27f65013efe1a4e966b21bd67d2a8b563ea28c2989
font_01_sfnt_off000106f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106F1 11012 bytes
SHA-256: b0a35919657deedd3a48d025103824bdac42b199a2255554c420a0054f8055ab
font_02_sfnt_off0001205e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1205E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1