Malicious PDF — malware analysis report

Static analysis result for SHA-256 7a3f42c1e52c85ad…

MALICIOUS

PDF

80.4 KB Created: 2021-09-07 14:10:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 00f5d21950a0a242ece989851312fe5f SHA-1: 375722024226103f30c0904fa9e8b46d678b3569 SHA-256: 7a3f42c1e52c85addfef226334025b90b49c068d8eb603e4bbd02c0932cdddc0
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised upload storage or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 7

  • 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.
  • 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://doellefjelde-mussemarked.dk/images/newsmail/file/latexatunibi.pdf In PDF document text
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160ad986184355---1908084130.pdfIn PDF document text
    • http://sk-uralstroy.ru/uploads/files/60253656168.pdfIn PDF document text
    • http://jvcc.cn/ckfinder/userfiles/files/210613145939502101rdrjk.pdfIn PDF document text
    • http://portaldeaquidauana.com.br/ckfinder/userfiles/files/xasixu.pdfIn PDF document text
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/29ee0e3e9eb6119dddeda6ad228a69d4/44152377035.pdfIn PDF document text
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/160e130b1d19ef---84756166996.pdfIn PDF document text
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16078ca852c199---losawik.pdfIn PDF document text
    • http://ankamet.com/userfiles/file/49686701144.pdfIn PDF document text
    • https://www.guestquesttravelmedia.com/wp-content/plugins/super-forms/uploads/php/files/p74j2ua5g5pqs8l8jnt31pd4fe/fizozujomemosiwix.pdfIn PDF document text
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608e72165b96d---bonakidiwegipufog.pdfIn PDF document text
    • http://efuegypt.org/userfiles/file/38630542606.pdfIn PDF document text
    • http://abwva.com/uploads/files/nixewerubi.pdfIn PDF document text
    • https://oceanflowerhotel.com/uploads/image/files/wexuzipiwija.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/2027a758e34461353a1061f9ac6d009a/vavasesudewosulazurisiru.pdfIn PDF document text
    • https://norservis.com/files/files/62151582904.pdfIn PDF document text
    • http://www.k-24.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079b84dbaa14---duzuwo.pdfIn PDF document text
    • https://floridainvestment.cz/files/file/96187003051.pdfIn PDF document text
    • http://www.pavimentosyreformasferlu.es/ckfinder/userfiles/files/matonupobesurep.pdfIn PDF document text
    • http://www.jacenter.org/js/ckfinder/userfiles/files/40184852508.pdfIn PDF document text
    • https://ferropula.hr/files/mazigejenisawa.pdfIn PDF document text
    • https://sakura-bashi.com/uploads/files/202108210531312350.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=five+forms+of+verbs+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_off0000d609.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD609 10432 bytes
SHA-256: b7ccda9f67baa076faa4c133a26b0b58f34f1cce69fd2049aeb7c452d15df3ec
font_01_sfnt_off0000ed71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED71 18016 bytes
SHA-256: c6fd2de601453c4388a046a0bf9392633ac84036786a8b33c466fb778bb7eac5
font_02_sfnt_off00011bc7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BC7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1