Malicious PDF — malware analysis report

Static analysis result for SHA-256 9c836f8b1dad0798…

MALICIOUS

PDF

77.8 KB Created: 2021-08-23 16:02:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: e607ae3c33a73b26a7e1d9949fa27e94 SHA-1: d391ce2da4ad02c674a3b69fa6f093b3ee4fe77e SHA-256: 9c836f8b1dad07986c170481807bf3be61c3b711096dbf75978f4168ca3b824e
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing or malware distribution sites. The embedded JavaScript is a common method for initiating malicious actions within PDF documents.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://foxtailmag.net/wp-content/plugins/super-forms/uploads/php/files/4a4675240e427bf758d759d7b698aeac/94814976639.pdf In PDF document text
    • http://hzdsbg.com/uploadfile/1620551038.pdfIn PDF document text
    • http://kiavysocina.cz/UserFiles/File/32854875068.pdfIn PDF document text
    • https://daismene.it/file/39563097893.pdfIn PDF document text
    • https://nhakhoaanphuoc.vn/uploads/files/89095364552.pdfIn PDF document text
    • https://mediabandit.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b5d9f4ab9e---44725281035.pdfIn PDF document text
    • https://keiba-like.biz/js/ckfinder/userfiles/files/35173793411.pdfIn PDF document text
    • https://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/df6de458adea6d4f9376b76de1377c65/10433634749.pdfIn PDF document text
    • http://chaukitchen.com/uploads/files/rapofakoworefosiwubu.pdfIn PDF document text
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607dc9ffbb23e---xigediwe.pdfIn PDF document text
    • http://sincaremedicaltour.com/js/upload/libipofubomazenarigebo.pdfIn PDF document text
    • https://www.cedicar.com/wp-content/plugins/formcraft/file-upload/server/content/files/161008a12118d1---47395911164.pdfIn PDF document text
    • https://www.urban-quartz.co.uk/wp-content/plugins/super-forms/uploads/php/files/ff654704d3e77d8dc65ec1b13ded0366/59438465402.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4a8dc3d71d---lojawigitezus.pdfIn PDF document text
    • https://trsbarriersdirect.com/wp-content/plugins/super-forms/uploads/php/files/0mdvg227j0disd0bmq4fjkcs2p/kuxesopitimukuwa.pdfIn PDF document text
    • http://cbcom.eu/ressource/site-image/files/delubu.pdfIn PDF document text
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d60c789f80---87405377207.pdfIn PDF document text
    • http://greenlivinggarden.com/htdocs/UserFiles/file/57442972509.pdfIn PDF document text
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dcc1e83cec---lutigidujumamodatirujido.pdfIn PDF document text
    • https://fotoprint.lv/downloads/file/tafegowojivavu.pdfIn PDF document text
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/7f8fd6c073650588795dc4895e0ce968/tuburedilakaregemij.pdfIn PDF document text
    • http://unsersohn.ch/images/file/bowitimoparidebi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=fate+stay+night+heaven%27s+feel+2+kissanimePDF 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_off0000ca36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA36 10844 bytes
SHA-256: ec02357dcdedeec9dd18d9ba0d1665235a0610cdb73255b0469a4a4929b0efca
font_01_sfnt_off0000e333.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE333 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fb45.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB45 16824 bytes
SHA-256: 8622e3fba62314d7b3b76a430f73212034a9de7b2ed0b8cfaf5b8baad2413863