Malicious PDF — malware analysis report

Static analysis result for SHA-256 9c2178022973750a…

MALICIOUS

PDF

70.6 KB Created: 2021-09-17 18:10:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: fb8c49c50f033c214c809205a422cfe0 SHA-1: f7029f47bbd1350f1508c5fe0541125244f254b1 SHA-256: 9c2178022973750a598d1686d9a84b96117595414c973000970d3603dc0bf6ef
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to external PDF files hosted on various domains, some of which are flagged as compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution through these linked documents. The 'link farm' heuristic suggests a tactic to artificially inflate search engine rankings or distribute payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://bruceleevideos.org/images/file/xomamedojutitedixo.pdf In PDF document text
    • http://gryfarmerskie.pl/pliki_wyswig/files/dewojimegadirakumanis.pdfIn PDF document text
    • https://ww150002.linebot.net/upfile/files/20210917031416.pdfIn PDF document text
    • http://hadt.vn/upload/files/1006149928.pdfIn PDF document text
    • https://innovaciones-plasticas.com/imagenes_cont/sitio/documentos/biwekijivukijugolam.pdfIn PDF document text
    • https://argekaucuk.com/nbg/upload/files/sasefotagukijosigurixu.pdfIn PDF document text
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/096c5c8bde7d5e6fd703f632614921ce/90186812305.pdfIn PDF document text
    • https://artofsurfing.com/preview/ckfinder/userfiles/files/lewagabekivigilof.pdfIn PDF document text
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/976dac36e53528f6cc51a85528fa8f05/22960180590.pdfIn PDF document text
    • http://bluecars.pl/userfiles/file/62675008287.pdfIn PDF document text
    • http://ambvetesopo.eu/userfiles/files/pojowexo.pdfIn PDF document text
    • http://artmetinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d9950a3f1b---fifom.pdfIn PDF document text
    • https://bcbc3399.com/upload/files/milafisojebikuxobi.pdfIn PDF document text
    • https://epagneuls-bretons.fr/caningest/images/file/legawebupefododarakos.pdfIn PDF document text
    • http://go-trec.com/wp-content/plugins/super-forms/uploads/php/files/5hpnsao0mv3d1l3cp4j1qvkv9i/17889951563.pdfIn PDF document text
    • https://mbbs.hr/files/46686698794.pdfIn PDF document text
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161305a18a818b---vilasekofuzip.pdfIn PDF document text
    • http://topenglish.sk/app/webroot/gallery/files/94350538584.pdfIn PDF document text
    • http://fence-alarm.com/userfiles/files/23293003346.pdfIn PDF document text
    • http://enricobarraco.com/files/67713310541.pdfIn PDF document text
    • http://autowagon.it/userfiles/files/rezeloroxutolirofowizet.pdfIn PDF document text
    • https://bacninhonline.com/webroot/img/files/62257178986.pdfIn PDF document text
    • http://bibikid.ru/upload/34230349255.pdfIn PDF document text
    • https://srmhomes.com/images/bulk_images/files/risawirij.pdfIn PDF document text
    • http://lovec.bg/root/ckfinder/userfiles/files/44486625711.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=mod+clash+of+clans+hackPDF 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_off0000b6b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB6B6 10236 bytes
SHA-256: 81f331601143e1a9776783940dbfc82c1557a2cae1024001b0ffdb45e5f25829
font_01_sfnt_off0000cd9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD9B 15420 bytes
SHA-256: a7a8362b002239df325aa115df42f9f4b9faa5c703378d39181d58c2babf9641
font_02_sfnt_off0000f4f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4F3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1