Malicious PDF — malware analysis report

Static analysis result for SHA-256 a2a8556aba083404…

MALICIOUS

PDF

83.6 KB Created: 2021-07-16 21:01:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 89f3babb7f21a17c01c1a9a604eff6a3 SHA-1: 75035645227728c5d51841f6cfcfce82780bb928 SHA-256: a2a8556aba08340494b1cb810ccda2500a50c7c56142717f1918cb1bc2180bd3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to numerous compromised WordPress sites, as indicated by the 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristics. The ML classifier and ClamAV also flagged this PDF as malicious, specifically as a phishing trojan. While no scripts were directly extracted, the nature of the link farm suggests an intent to lure users to malicious content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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.justgym.co.za/wp-content/plugins/super-forms/uploads/php/files/u5mr05uirk1pque5esatmce8qs/43667670814.pdf
    • https://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/9197866a006d1a6a96694c6f87eb87a2/1536846845.pdf
    • http://www.sec-ollivier-associes.fr/www/upload/file/63040059137.pdf
    • http://boeschfamilytravels.com/clients/43210/File/risisepinekinamiwereb.pdf
    • http://handbook.hu/upload/page/file/26760844702.pdf
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aeff15db74c---porusoriwajazadavuf.pdf
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/ccd99ec1a5d5d89abf7c7ce01171048d/sasirenafefelalanuwedi.pdf
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/ji8tj4kbm1hj793fnckbdl48l1/zamobalavuxajarave.pdf
    • http://call.ae/wp-content/plugins/formcraft/file-upload/server/content/files/160a96038a300c---vetevupabivivobobide.pdf
    • https://familienbilstrup.dk/userfiles/file/87392121441.pdf
    • https://ewt.cz/res/file/84104190338.pdf
    • http://www.agrosystem.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160928549a1303---kikaradukenipoji.pdf
    • http://kashima.cc/userfiles/file/xonagana.pdf
    • http://faradbox.pl/files/file/8902742038.pdf
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16073ecef21130---wunibide.pdf
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2d544e79e6---wikuwazuk.pdf
    • https://connect.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/f128b3f9aea3c1069049eb2094c9bb43/fegub.pdf
    • https://cakenepal.com/userfiles/file/zobozunokijepusexito.pdf
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ae1276d49b---88460998097.pdf
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/cee9b8242b7d51cf29590566e8b7b403/sotarakep.pdf
    • http://www.yoko-ono.be/images/userfiles/file/milojewezapozawe.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=easy+drawing+of+a+well
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e565.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE565 16792 bytes
font_01_sfnt_off0000fd7c.bin
a4b31899cc286a98085e3cd3a90c9cbeeaf9ce4eb1073267684daa274a46bf9e
pdf-font-stream PDF embedded font (sfnt) at offset 0xFD7C 10616 bytes
font_02_sfnt_off000115b1.bin
136aab40b147376ea4d31caba6f5cad83d15b5533d39541398d957b3254d10e4
pdf-font-stream PDF embedded font (sfnt) at offset 0x115B1 16780 bytes