Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd6550461cd72d61…

MALICIOUS

PDF

84.9 KB Created: 2021-09-06 02:47:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: c9b7103a90d2420edd90cf58f7c157be SHA-1: a94447742c7339317418253ac7c2835f9e114668 SHA-256: cd6550461cd72d61988e027b42ba19eff818c2c5b76751fd8334676d9280a6d8
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains embedded JavaScript and a large number of external URIs, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users. The primary purpose appears to be directing users to malicious sites, likely for phishing or to download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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 http://salukool.ee/upload/userfiles/file/85454026274.pdf In PDF document text
    • https://scapetime.net/images/website/user/files/fakafelinon.pdfIn PDF document text
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a921f0bc3de---resetuximotekim.pdfIn PDF document text
    • http://airfa.it/userfiles/file/93896017507.pdfIn PDF document text
    • http://penzion-u-zamku.cz/files/file/zegulokufomotedovuke.pdfIn PDF document text
    • https://betenrealestate.com/sites/default/files/file/32454025522.pdfIn PDF document text
    • https://oykufestivali.com/ckfinder/userfiles/files/16821614126.pdfIn PDF document text
    • http://jikaramen.com/uploads/files/53220189875.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160b0841db8220---25777834534.pdfIn PDF document text
    • http://championsview.net/userimages/96077665940.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c158a92401c---zokudajefubumakewipeza.pdfIn PDF document text
    • https://autoschiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/160703dc72b94a---25885727636.pdfIn PDF document text
    • http://topcudental.com/img/userfiles/files/zutorakemigigibusaziwofe.pdfIn PDF document text
    • http://amako-ra.com/wp-content/plugins/super-forms/uploads/php/files/6cced2c81fc26f41290c2467ffe16be1/76220542370.pdfIn PDF document text
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/242o1a49mue4me3dfcab0mq9c5/78007455568.pdfIn PDF document text
    • https://hmv.ir/wp-content/plugins/formcraft/file-upload/server/content/files/1606d92ad7dee7---85406643501.pdfIn PDF document text
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/0e2981b17ddf1db38ca5d36b9aeead38/fumomosukajiwukixoxako.pdfIn PDF document text
    • http://villaturri.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093d88e1b95d---70585480692.pdfIn PDF document text
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/160db129976cff---15528865131.pdfIn PDF document text
    • http://w-f-l.de/user_img/file/14054294835.pdfIn PDF document text
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/160d18ea70f614---xosibiwanoz.pdfIn PDF document text
    • https://uetty.xyz/js/ckfinder/userfiles/files/voregafipa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=bus+station+design+pdfPDF 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_off0000e85d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE85D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001006f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1006F 17380 bytes
SHA-256: ecb4eaf7df3260361068ecb8616ee087096e981d142869fb91984240faf49a05
font_02_sfnt_off00012d85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D85 10680 bytes
SHA-256: 437f298fe684e48b401d90c47233b7edd1802625d8d104088a2896deaa7cce23