Malicious PDF — malware analysis report

Static analysis result for SHA-256 b57890bc94d517c3…

MALICIOUS

PDF

71.8 KB Created: 2021-06-09 21:33:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-05
MD5: ef5bd57f845748d4fb93d2e20847d135 SHA-1: 56867b2c86b390d5a50e820ab9ea3620e96f03b4 SHA-256: b57890bc94d517c3fdd1dbd22af5c787e6de44a454642023b6d76dab966e9f95
164 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links to compromised WordPress upload directories and disposable hosting sites, suggesting it's part of a link farm designed to distribute malware. The presence of a visual download button further supports the lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://infrive.ru/uplcv?utm_term=mp3+song+gallan+goodiyaan PDF link annotation
    • https://its-bulgaria.bg/files/file/28987655139.pdfIn PDF document text
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160802ad2ebbc6---janotifusadoda.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160baf0e59bdf7---litadulosumepewedavulul.pdfIn PDF document text
    • https://prikolnaya.com/wp-content/plugins/super-forms/uploads/php/files/9ba02d9d0a1a627cd533eb6c10e0ab25/doxem.pdfIn PDF document text
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb538e1b66---pipopajado.pdfIn PDF document text
    • https://mobistore.co.nz/wp-content/plugins/super-forms/uploads/php/files/8397b6efc6141bde560f4c4685b47ee7/10041054776.pdfIn PDF document text
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acb8a051bd4---82669127220.pdfIn PDF document text
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/abdbd5e4a471e1a4d1bc33e0cdb34533/jovupusax.pdfIn PDF document text
    • http://xboxheerlen.nl/userfiles/file/59924321874.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/95581becaeb93ff0010c790167d069ab/jilid.pdfIn PDF document text
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e0bb8bf99a---zizipivewo.pdfIn PDF document text
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160bbab52ca411---redalanug.pdfIn PDF document text
    • https://him-home.ru/wp-content/plugins/super-forms/uploads/php/files/2f140d57ce3476eb07ff676de714c84f/61900894230.pdfIn PDF document text
    • http://novussiteyonetimi.com/uploads/file/lulenoseziga.pdfIn PDF document text
    • http://call.ae/wp-content/plugins/formcraft/file-upload/server/content/files/160a5fcf817863---lagajixuwitokikajaf.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dc01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC01 5304 bytes
SHA-256: 271b725cc93cd30ec6cc11edfe586880ed61a3abd8babb2e211a1667965ee0cc
font_01_sfnt_off0000ee30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE30 11032 bytes
SHA-256: f0135d641adfb02c79701e174c076fd051712283e14b09b53c60f731679cf60d