Malicious PDF — malware analysis report

Static analysis result for SHA-256 cdb399ba01b8b638…

MALICIOUS

PDF

81.4 KB Created: 2021-09-08 17:34:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 04bc1adfa3cb49a24ea9f0f141806e18 SHA-1: b355e365a6a1116c17c167645a4c2aa1b7faf83d SHA-256: cdb399ba01b8b638c2365c75fa762f0f9b11836b9449539ec193ffd478a9ce87
184 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple heuristics indicating it's a link farm, with several URLs pointing to potentially compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were directly extracted, the PDF structure and embedded URIs are indicative of a phishing or malware distribution lure, likely leveraging T1566.001 (Spearphishing Attachment) as the initial access vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://onderdurdu.com/upload/ckfinder/files/juzodavaf.pdf In PDF document text
    • http://uitvaartverzorgingsindex.nl/images/uploads/41005631311.pdfIn PDF document text
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/16132e1a32f99f---jawexo.pdfIn PDF document text
    • http://185.33.116.145/~acus01/upload/files/56365386918.pdfPDF link annotation
    • http://myconnect-thailand.com/image/upload/File/guzevajeba.pdfIn PDF document text
    • https://samudra99.com/contents/files/22974745824.pdfIn PDF document text
    • http://fongyoskert.hu/userfiles/files/pelojaxekalabarepas.pdfIn PDF document text
    • https://riosemarescentrodemergulho.com/ckfinder/files/jizavaratotikofagojir.pdfIn PDF document text
    • https://keluargamimpi2.com/contents/files/20019447764.pdfIn PDF document text
    • http://ebara.com.hk/ckfinder/Zenith/userfiles/files/11637195269.pdfIn PDF document text
    • https://morethancars.eu/uploads/edytor/file/87604961913.pdfIn PDF document text
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/16137402a6e32d---29755814403.pdfIn PDF document text
    • http://mishor-uvk.com/uploads/files/dijodagubamuresosifekimaz.pdfIn PDF document text
    • https://esperanzadeavila.com/fotos/file/xurosipomijebivogarex.pdfIn PDF document text
    • http://packturf.fr/files/7819767176.pdfIn PDF document text
    • https://deltarealestate-eg.com/userfiles/file/naguzedolazowajesuzijew.pdfIn PDF document text
    • http://kadh.kr/bobod/upload/file/7995065263.pdfIn PDF document text
    • http://packturf.fr/files/68912662677.pdfIn PDF document text
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132808017b77---joriwediz.pdfIn PDF document text
    • http://cinebuzz.be/uploads/userfiles/files/15449187437.pdfIn PDF document text
    • https://cargotavio.ru/files/file/sodujonigoni.pdfIn PDF document text
    • http://thanhtindesign.vn/uploads/image/files/14213226579.pdfIn PDF document text
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fbf94a57c3---gewetetivovajuxorivimi.pdfIn PDF document text
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/p26rsddl5kccti7sqiv565bv52/gukerow.pdfIn PDF document text
    • http://kondicionery-shodnya.ru/upload_picture/file/84522558849.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=pdf+editor+download+free+for+macPDF 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_off0000d700.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD700 18760 bytes
SHA-256: 1a92c8111477b51c6545285d5439a549db1115a638fb70e8c2e68a1ce76142dd
font_01_sfnt_off000107c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107C9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011fe0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FE0 10556 bytes
SHA-256: 71b45f91ef94a4da7a060437e466cd194475b99c167010071384cc69a6ea2bcd