Malicious PDF — malware analysis report

Static analysis result for SHA-256 4129a8cd9b91e8bb…

MALICIOUS

PDF

93.7 KB Created: 2021-07-02 14:59:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: ee17edbbb359cb4403218a087f54beb8 SHA-1: 3785e896ab56eefb6ab71996d0a9bbff03ce4662 SHA-256: 4129a8cd9b91e8bbfbb39df483bfb846c9d93b70bf5ec287383fff323d435c02
156 Risk Score

Malware Insights

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

The PDF document contains numerous links, many of which point to compromised WordPress sites and other disposable hosting. The ClamAV detection and ML classifier strongly indicate malicious intent, likely to phish users or lead them to malicious content. The document body is unreadable, but the heuristic firings clearly show a link farm designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9820

Heuristics 6

  • 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.
  • 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://abe-rdc.com/userfiles/file/20799690934.pdf In PDF document text
    • http://imailbox.nl/images/uploadedimages/file/85575083163.pdfIn PDF document text
    • https://celovechurch.org/wp-content/plugins/super-forms/uploads/php/files/faf68d66e3aaacb2852abcbf8bf4849e/dukom.pdfIn PDF document text
    • http://christembassydocklands.org/wp-content/plugins/super-forms/uploads/php/files/bc69ff694d1a732d8c76812193c667cb/57051818727.pdfIn PDF document text
    • http://dabaizhongxue.com/upload_fck/file/2021-5-12/20210512002642677953.pdfIn PDF document text
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/so7amj8fkaegfqanpfi6c98uuo/62052548720.pdfIn PDF document text
    • https://elpmarketing.ca/wp-content/plugins/super-forms/uploads/php/files/23eb17cfaf213e4130d411ec8c6c28f3/12110140281.pdfIn PDF document text
    • http://www.allatpatikapecs.hu/images/file/72382917237.pdfIn PDF document text
    • http://aliceinformaticasrl.com/user/pages/jatuzogitumubavozid.pdfIn PDF document text
    • http://af.ssla.ru/images/fornews/files/womizad.pdfIn PDF document text
    • https://asset-books.com/userfiles/file/loxinur.pdfIn PDF document text
    • https://thekolkatapackersmovers.com/ckfinder/userfiles/files/pusavupe.pdfIn PDF document text
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9adb8675fe---39196540711.pdfIn PDF document text
    • http://archerelectricsupply.com/userfiles/file/47510104546.pdfIn PDF document text
    • https://cqc-material.com/app/webroot/userfiles/files/27954575814.pdfIn PDF document text
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b7f0d57f442---97170531875.pdfIn PDF document text
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076efbc97d2d---bivivanipi.pdfIn PDF document text
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2c01078b9c---kowonosirurezoguzonobiw.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b488db873bc---94613218761.pdfIn PDF document text
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/2204b287dc55b93155b192d91693be07/tojijapopitezebos.pdfIn PDF document text
    • https://www.accidentinjuryalbuquerque.com/wp-content/plugins/super-forms/uploads/php/files/eiib9sgei0ad2ma00rsrlmgeqt/96111584852.pdfIn PDF document text
    • https://shotclock.ca/wp-content/plugins/super-forms/uploads/php/files/087b7b51a9a5f7264c43bc74afd3bbfc/rekatetoz.pdfIn PDF document text
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f596dd0bf2---58688214239.pdfIn PDF document text
    • https://sipare.com.ar/wp-content/plugins/super-forms/uploads/php/files/olc8gcsbo3rubd0kfo5dga6lv6/40072636206.pdfIn PDF document text
    • https://1877painters.com/FCKeditor/file/60299167974.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/e77d1921ceecfbccfb85608cdf05754c/63536163146.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=short+story+on+practice+makes+a+man+perfectPDF 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_off00010c76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C76 16636 bytes
SHA-256: 89526797b7e2ed3166e030ec070594ef045ccea448e84d7db68db7ca9b767393
font_01_sfnt_off0001376c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1376C 10980 bytes
SHA-256: 4294f943e759a21cdfe1e92c060f095278890e75e34541f021eba9fae7857b04
font_02_sfnt_off000150c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x150C8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1