Malicious PDF — malware analysis report

Static analysis result for SHA-256 3497ba2e7d06f9eb…

MALICIOUS

PDF

73.4 KB Created: 2021-09-22 13:16:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 90761f58fb4dee670e5cb3742ade06af SHA-1: 03c1aca3dece5052b4e4b51586f9f145aec78872 SHA-256: 3497ba2e7d06f9eb86abf27b22026f8fdb16ee086ea018bf96d04ff06d262c8d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file is identified as malicious by ClamAV and an ML classifier, with heuristics indicating it functions as a link farm pointing to compromised CMS uploads and disposable hosting. The presence of multiple external URIs, some of which are associated with compromised WordPress sites, suggests an attempt to redirect users to malicious content. The document body is heavily obfuscated, preventing analysis of its specific content, but the overall structure and heuristic firings strongly indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://athensviptour.com/wp-content/plugins/super-forms/uploads/php/files/69034193bb250ef022d4022d3cebf926/58245437119.pdf In PDF document text
    • https://artofsurfing.com/preview/ckfinder/userfiles/files/dotefe.pdfIn PDF document text
    • http://deborahkay.com/ckfinder/userfiles/files/lajezovapitefasopuk.pdfIn PDF document text
    • http://househouse.it/userfiles/files/vemukujunemiwonira.pdfIn PDF document text
    • https://mkontroll.hu/File/getebufekaxufizizewilobi.pdfIn PDF document text
    • http://www.siposferenc.hu/html/80445405641.pdfIn PDF document text
    • http://vako.vn/app/webroot/uploads/files/23291454323.pdfIn PDF document text
    • https://cosmopolitanhotelbg.lastrada.bg/uploads/wysiwyg/files/dutek.pdfIn PDF document text
    • http://wijnhuis-vaessen.nl/site/data/ws/files/83884441278.pdfIn PDF document text
    • http://zulassungsservice4you.de/bilder/file/23356939078.pdfIn PDF document text
    • http://fusiongrup.ro/userfiles/file/vubudusilosikexaj.pdfIn PDF document text
    • https://qfse.co/images/uploaded_files/ckfinder/files/1632304109_2c7a509a4a.pdfIn PDF document text
    • https://congtydaihai.com/upload/files/zuxeruv.pdfIn PDF document text
    • https://medosojewellery.com/userfiles/files/tiraxow.pdfIn PDF document text
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/161359684195bc---texifozupogug.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614af00a717a1---leratikatotas.pdfIn PDF document text
    • http://xn--80aamwn.xn--p1ai/userfiles/file/semebawiwajudomakevopes.pdfIn PDF document text
    • http://szerecsengyogyszertar.hu/editor_up/bebutifiwamumuwivale.pdfIn PDF document text
    • http://czerwoneiczarne.pl/files/file/1980378875.pdfIn PDF document text
    • https://kamarkosong.com/contents/files/2607188116.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=pubg+kr+1.0+0+updatePDF 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_off0000bd3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD3B 16816 bytes
SHA-256: aeeb63b6b78693a67d29e21f8746b38cf4fa372390b4d9aa8b351488b2d30cdf
font_01_sfnt_off0000e86d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE86D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010084.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10084 10612 bytes
SHA-256: 455fc12dca42dbbdbdfd13c9ac86a42b30180e6f340b05180f7b4a456dd0a241