Malicious PDF — malware analysis report

Static analysis result for SHA-256 e6fec365879981af…

MALICIOUS

PDF

104.7 KB Created: 2021-09-07 06:13:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: a5c6f39ddef4e3e4f161149ee5643b33 SHA-1: b19f7db1d51f1174d5051c90429d999ade9dae0f SHA-256: e6fec365879981af9085630eea70a5ff0c0ac1f7fcbf3bbd32b751d8b2fc8ea5
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many of which point to compromised WordPress sites. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution through these links. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, providing no direct user-facing content but serving as a container for the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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 http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/e3qhbe36sk7tmornptbk2804v2/41795323644.pdf In PDF document text
    • https://intrastorg.com/userfiles/file/86196828340.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1606f8c36e5cb2---gajumefasukagobe.pdfIn PDF document text
    • http://silesiacapital.eu/data/file/nabibejepupowu.pdfIn PDF document text
    • https://maugli24.ru/wp-content/plugins/super-forms/uploads/php/files/730a1ab8624357e4dacb3522248f39bc/sapobarigakefagoweropafob.pdfIn PDF document text
    • https://kassa-evotor.ru/wp-content/plugins/super-forms/uploads/php/files/d55h1utd3hjn3h0r1o6sd0lm35/zuxobodimuzenut.pdfIn PDF document text
    • https://harryfok.com/ckfinder/userfiles/files/kitawise.pdfIn PDF document text
    • https://www.northwoodmedical.ca/wp-content/plugins/super-forms/uploads/php/files/oj8idpc81m8n8617m3sckidp4o/46122938257.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a192141ef2f---zexibezejuzetufip.pdfIn PDF document text
    • https://acethamessecurity.co.uk/wp-content/plugins/super-forms/uploads/php/files/cdb4d6f96647a50c0d68c73acfb35e8a/sijovitoja.pdfIn PDF document text
    • https://seltec.io/images/uploads/files/204290651.pdfIn PDF document text
    • http://streetnn.ru/data/upload/ck/files/28704319444.pdfIn PDF document text
    • https://pataniforum.com/admin/jquery/ckfinder/userfiles/files/boxazasivisaf.pdfIn PDF document text
    • https://thuaphatlaihanoi.net/uploads/files/98444529361.pdfIn PDF document text
    • https://deltarents.com/upload/ckfinder/files/5377684646.pdfIn PDF document text
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/53e81183e9d2aeb6305494413211a8a8/lasulezur.pdfIn PDF document text
    • http://bukharageorgia.com/sites/default/files/file/41394843809.pdfIn PDF document text
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/mbindqpv54avue9hnv95qf5l9n/71158111232.pdfIn PDF document text
    • https://ivfnna.gr/wp-content/plugins/super-forms/uploads/php/files/f681ce1e743d1a4fd934fb02d9b90d9a/jolajolore.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160b63b1233e90---nuramazekapefikivuwireso.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607901d5af2dc---tinisixoxafimozowodotilof.pdfIn PDF document text
    • https://candbco.com/ckfinder/userfiles/files/21230125330.pdfIn PDF document text
    • http://jrpst.pl/userfiles/file/67592191175.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=squares+and+cubes+upto+100+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_off00012c3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C3C 11108 bytes
SHA-256: e82c79c4c9d82f76378d085e13a6134b431308e2eef0c14091dde86da9e364af
font_01_sfnt_off000145dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x145DD 21848 bytes
SHA-256: 7287fa94a0ff61ba00714786237690dccfc6e1c1d7168d2feabac649373980e9
font_02_sfnt_off00017d06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17D06 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1