Malicious PDF — malware analysis report

Static analysis result for SHA-256 15fcde552b4e61ec…

MALICIOUS

PDF

104.9 KB Created: 2021-06-25 13:43:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: c169c141bb022fe2d7e7c345d2bafef9 SHA-1: beb89fbbbc0ea91079764621738bbe8536bac3a8 SHA-256: 15fcde552b4e61ecfafad3cf649ec5c2db89b88322e58cd22733988f73e39478
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users. The embedded JavaScript likely facilitates the redirection to these malicious URLs, potentially for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

Heuristics 7

  • 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.
  • 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://catamma.ru/uplcv?utm_term=number+of+atoms+in+sodium+sulphate PDF link annotation
    • https://estidevelopers.com/wp-content/plugins/super-forms/uploads/php/files/7bbe6559bcbb92acedafde893a496aee/41875940667.pdfIn PDF document text
    • https://ev-owners.jp/userfiles//files/xidakuvupobuvinuxobodifog.pdfIn PDF document text
    • http://tgtech-auto.com/userfiles/file/7362342152.pdfIn PDF document text
    • https://kuzeyilac.com/resimler/files/55020420624.pdfIn PDF document text
    • http://bradleyhillsapartments.com/demo/uploads/contents/file/60347971703.pdfIn PDF document text
    • https://dezsredstvompx.ru/wp-content/plugins/super-forms/uploads/php/files/b661038dddcceea78590273e09dd8da4/71791651727.pdfIn PDF document text
    • https://floridaholidayplanner.com/wp-content/plugins/super-forms/uploads/php/files/06b1a2355036363d8489c978ad80fce4/67054633153.pdfIn PDF document text
    • https://www.ergunaygoren.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607aaac33915a---30127548306.pdfIn PDF document text
    • https://www.duffylighting.com/wp-content/plugins/super-forms/uploads/php/files/fe3091afe3ece394dc10bb6077c19350/39395954555.pdfIn PDF document text
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/b2896c66ca43a85170fa33eb3d1c3e02/sifaxigasajenozirolififo.pdfIn PDF document text
    • http://kaupa.cz/userfiles/file/18562550590.pdfIn PDF document text
    • https://cargotavio.ru/files/file/87117968734.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16092fa55c291c---58682412685.pdfIn PDF document text
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/apt9qn1e8v3ck8dvubqedv4an6/39936057356.pdfIn PDF document text
    • https://amitadevnani.com/userfiles/file/77515270045.pdfIn PDF document text
    • https://sfasg.jp/js/ckfinder/userfiles/files/63784892202.pdfIn PDF document text
    • 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_off00013698.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13698 10980 bytes
SHA-256: 5e7c3cf0d87a88f268bfeb3ca1eb725059165f5ddb2643cc5f10c175b7cced7c
font_01_sfnt_off00014f9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14F9B 17832 bytes
SHA-256: e73af9a4b90d37592379384aea96b09eced67071f6dabe7bd84290e25d9ae337
font_02_sfnt_off00017ebb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17EBB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1