Malicious PDF — malware analysis report

Static analysis result for SHA-256 2d658c121ff1857b…

MALICIOUS

PDF

87.4 KB Created: 2021-09-13 20:01:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 017b216944315254dd81fc68c5c059ce SHA-1: 4a0076a8aca6d04e749605649315a93c581b4d46 SHA-256: 2d658c121ff1857b191d98b77865c1e51a6fa739583257c57d89486643305d43
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ClamAV and an ML classifier, with heuristics indicating it's a link farm on potentially compromised or disposable hosting. The embedded JavaScript stream suggests an attempt to redirect users or execute further malicious actions. The numerous external links, many pointing to PDF files on various domains, indicate a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://thueotodn.com/uploads/image/files/fubogozekelupo.pdf In PDF document text
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613b1276b8c7c---bigaxodudij.pdfIn PDF document text
    • http://obkladlazby.cz/userfiles/file/43945632603.pdfIn PDF document text
    • https://sassanoproperties.com/FCKeditor/file/10645524645.pdfIn PDF document text
    • http://hoangminhphatkorea.com/webroot/img/files/bimavipuzu.pdfIn PDF document text
    • http://www.solarwindependence.com/ckfinder/userfiles/files/64476946783.pdfIn PDF document text
    • http://mdknoodles.co/uploads/files/sufemonixuwuviviboxusus.pdfIn PDF document text
    • https://soyana.de/js/ckfinder/userfiles/files/kilejulixofasuburawamup.pdfIn PDF document text
    • https://vzglavniki.net/data/file/1495675480.pdfIn PDF document text
    • http://sriraghavendratemple.com/ckfinder/userfiles/files/77879831175.pdfIn PDF document text
    • http://master-vin.ru/files/file/29623866345.pdfIn PDF document text
    • http://mkbeauty.vn/luutru/files/jizilozisupakoxerogukuvaf.pdfIn PDF document text
    • https://mediabandit.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e120d50696---xolugevososit.pdfIn PDF document text
    • http://cnsgawefgl.netsociality.com/upload/files/powawukarokaxakodaw.pdfIn PDF document text
    • https://k9-warrior.com/wp-content/plugins/super-forms/uploads/php/files/68mdker37n2gfnqsgv60lv3sn6/49985297132.pdfIn PDF document text
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613aedaf2b7da---bowuxesusakog.pdfIn PDF document text
    • https://beyondpins.com/calisma2/files/uploads/vemimejaxokelubawot.pdfIn PDF document text
    • https://costabravas.com/uploads/localidades/files/jekuxanelolekopot.pdfIn PDF document text
    • https://myclubowners.travelenvogue.com/userfiles/files/kovibu.pdfIn PDF document text
    • https://www.retake.dk/ckfinder/userfiles/files/10087643655.pdfIn PDF document text
    • http://sk-massimo.com/js/upload/files/57870700514.pdfIn PDF document text
    • https://www.hsbofmn.com/ckfinder/userfiles/files/lozemalo.pdfIn PDF document text
    • http://soundspace.eu/Upload/file/24345179721.pdfIn PDF document text
    • http://acupunctuuryao.nl/ckfinder/userfiles/files/jowasil.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=god+tube+apkPDF 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_off0000ef01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF01 10248 bytes
SHA-256: f91683489757c58050d221b1c9811d1ce72b51d9adf7dd771fb976bf40734490
font_01_sfnt_off000105eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105EB 19264 bytes
SHA-256: caf87d93c5e76af8033f4c4433986c0a9747bfe9b34cccee8e5bfab8ee90bfae
font_02_sfnt_off000137ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x137ED 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1