Malicious PDF — malware analysis report

Static analysis result for SHA-256 615943a0d6b6b375…

MALICIOUS

PDF

73.8 KB Created: 2021-06-25 22:28:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f7fe9ec3d4bc08a0f243dc87078b07f7 SHA-1: f4aab83603b5b5e289be5aa3bb9d9781d3263db1 SHA-256: 615943a0d6b6b37591e45a807f11f07b2735cd6a61c069cdcbb0a1f38cecb40f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous external links, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious content. While no scripts were explicitly extracted, the PDF structure and numerous URLs indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://synerhu.ru/uplcv?utm_term=how+to+make+wither+storm+minecraft
    • http://musorcentrum.hu/files/article/file/88399508939.pdf
    • http://archi1919.com/smlclub-files/file/xatoveniwowosav.pdf
    • https://beribuket.ru/wp-content/plugins/super-forms/uploads/php/files/d4b49dddd3699da3c1d901bd38ce1455/sikotasutilusur.pdf
    • http://apexibd.com/uploads/fck_uploads/file/58301093472.pdf
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609be5ddad2c7---dazonetujep.pdf
    • https://winston-woodward.com/wp-content/plugins/super-forms/uploads/php/files/aa5609349546b6df53d8c9ce285ef1b7/61134911496.pdf
    • https://bladmedyczny24.pl/wp-content/plugins/super-forms/uploads/php/files/baf3bf2246c7909e356e2054dc852a23/womirowojidizuvawakifoz.pdf
    • https://gbeequestriansurfaces.com/wp-content/plugins/super-forms/uploads/php/files/68po4s5j49pit8k6tdirecvpmf/29842634861.pdf
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/16080e9eeb835f---85919119043.pdf
    • http://skogsformedling.se/bilder_umeny/File/tumokunube.pdf
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607f84c08c892---kufijevotelufarox.pdf
    • http://aksaaydinlatma.com/img/editor/image/file/lirivopisitozutefefu.pdf
    • https://www.waterlooarmsnewforest.co.uk/wp-content/plugins/super-forms/uploads/php/files/190dd3a88e98b925937eab68255f2b2b/3472575414.pdf
    • http://knshzj.com/CKEdit/upload/files/makobitaxalurebibik.pdf
    • https://elektrona.cz/files/file/18946290048.pdf
    • http://plafondchauffant.fr//img/user/file/37588087205.pdf
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4a8d71afba---81512600693.pdf
    • http://iamsoldierfit.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075ebe4ba94c---24954425711.pdf
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c17c7cac4b8---45508176449.pdf
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076cb2d3ad47---donufadefenivob.pdf
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/5a20e71e96cfecee676c0f16309c5fcd/jikobujapewajobanovimi.pdf
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aba97854758---sepuwavonowuxanik.pdf
    • http://www.pianoszimmermann.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609915cc07f0b---kekefo.pdf
    • http://leesfeest.nl/leesfeest/sites/default/files/file/69332705614.pdf
    • 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_off0000becf.bin
67dae40a84e080dde04d16f9666297b1effb7856de1726b785d23fa03c647af8
pdf-font-stream PDF embedded font (sfnt) at offset 0xBECF 16468 bytes
font_01_sfnt_off0000e989.bin
b5d0f90878bd50779d7c57350b85f51f9084762779dc8e68358fa9c5cc984c92
pdf-font-stream PDF embedded font (sfnt) at offset 0xE989 10724 bytes
font_02_sfnt_off00010201.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10201 16792 bytes