Malicious PDF — malware analysis report

Static analysis result for SHA-256 51e0a6dbf6d62afd…

MALICIOUS

PDF

77.9 KB Created: 2021-09-01 12:15:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 802d2573d5077321b5f14beb868c20bf SHA-1: 2df784e800bc1e2154347b2ae87d3fdfecb9d094 SHA-256: 51e0a6dbf6d62afdbc2cc52afac898812b840077867e06927646763ab8ebe520
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to various domains, many of which are associated with compromised CMS uploads or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports the attack pattern of creating a link farm to distribute malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://crysiq.ru/uplcv?utm_term=quantum+of+solace+yacht PDF link annotation
    • https://leganordavigliana.it/uploads/file/xutada.pdfIn PDF document text
    • http://qhzs88.com/admin/fckeditor_upfiles/file/2021062615241680554.pdfIn PDF document text
    • http://alphabodysupplements.com/newerac2c/userfiles/file/86353365724.pdfIn PDF document text
    • http://bertrandetgastineaudesigners.fr/userfiles/file/57019020892.pdfIn PDF document text
    • https://auto-rujo.com/images-editor/file/57368365579.pdfIn PDF document text
    • https://alexandrapanayotou.com/web/images/static/file/rokabifexubexuj.pdfIn PDF document text
    • http://duythuc-bearing.vn/uploads/userfiles/file/kevenux.pdfIn PDF document text
    • http://orderkiwicafe.com/uploads/files/94213343643.pdfIn PDF document text
    • https://larustt.com/upload/ckfinder/files/wuzepuvufo.pdfIn PDF document text
    • http://asiadomainstore.com/userfiles/file/kofixezuzuvewaroxetuxakuz.pdfIn PDF document text
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c094841787e---wenozapalewewaravisaz.pdfIn PDF document text
    • https://china-glass-mosaic.com/userfiles/files/20210721_082916.pdfIn PDF document text
    • http://smn68.com/clients/75339/File/68363315680.pdfIn PDF document text
    • https://aquafilling.com/userfiles/file/85072392490.pdfIn PDF document text
    • https://teamcode.net/upload/files/53145503862.pdfIn PDF document text
    • http://denki-shonan.com/uploadsfile/91883190404.pdfIn PDF document text
    • http://espressoperfetto.nl/app/webroot/files/userfiles/files/75370319572.pdfIn PDF document text
    • http://bukharaalpharetta.com/sites/default/files/file/23539088270.pdfIn PDF document text
    • https://0286869143.com/editor_images/files/xowisibosiv.pdfIn PDF document text
    • https://refour.dk/wp-content/plugins/super-forms/uploads/php/files/0e6145f087ab2f553929d13947b2cc0a/58574898296.pdfIn PDF document text
    • https://sealskinz.ru/files/file/kadipin.pdfIn PDF document text
    • http://kennyre.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4268814be7---bumupovanoju.pdfIn 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://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_off0000cdbc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDBC 17164 bytes
SHA-256: c3f89a18a0b7a054c08720b62239fa1992776a91e7b63f992659d96c6dcf3693
font_01_sfnt_off0000fa53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA53 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001126a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1126A 10684 bytes
SHA-256: 8a08360e29f440d06db0cbb8edd5c08aaafc5b560ec6bc868fd50de0d0e13935