Malicious PDF — malware analysis report

Static analysis result for SHA-256 51423148356b59c7…

MALICIOUS

PDF

80.6 KB Created: 2021-09-06 04:58:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: acf744202a63a5771bbd0096583f9ef2 SHA-1: c675f0d1dee469f5177ec7bf242be5a347d67e3c SHA-256: 51423148356b59c7939d85c41498787c262ef449fb9aea59913f73281ffc3238
164 Risk Score

Malware Insights

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

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised CMS upload directories and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and unreadable, preventing a detailed analysis of its specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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 http://aarogyamedico.com/userfiles/file/50751345247.pdf In PDF document text
    • https://mintedimages.com/ckfinder/userfiles/files/sumoxijezijipug.pdfIn PDF document text
    • http://dakmet.pl/upload/39381131908.pdfIn PDF document text
    • http://flygarfield.net/userfiles/file/31989257329.pdfIn PDF document text
    • http://pasaru.com/upload/files/80278040650.pdfIn PDF document text
    • http://africansafaris-spain.com/FCKeditor/editor/filemanager/connectors/php/connector.php?Command=FileUpload&Type=File&CurrentFolder=%2Ffile/7718468075.pdfIn PDF document text
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/eb6c49416c3c68285f2db71d2dcbecb6/roxareniwunabovod.pdfIn PDF document text
    • http://ankamet.com/userfiles/file/85506934943.pdfIn PDF document text
    • http://niestachow.pl/data/aktualnosci_imgs/file/316317336.pdfIn PDF document text
    • https://beaufortbond.com/wp-content/plugins/super-forms/uploads/php/files/39bde5ab009a54a60d865510fa05ceaa/36169351478.pdfIn PDF document text
    • http://vning.net/filespath/files/20210825032151.pdfIn PDF document text
    • http://yer-krasnodar.ru/ckfinder/userfiles/files/litow.pdfIn PDF document text
    • http://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/f48ibmua9mi2nnvq3mkq7cbef6/fudumela.pdfIn PDF document text
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/160802173b9f23---xudit.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609df3ea930db---36210652892.pdfIn PDF document text
    • https://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/7l2jjcse5tq1peovpafgvs73k5/66299372274.pdfIn PDF document text
    • https://408of53crownstreet.com/assets/media/files/99370658317.pdfIn PDF document text
    • http://nw-line.ru/generic/uploaded/57796388813.pdfIn PDF document text
    • http://ranaghatpchsschool.org/userfiles/file/bapibedar.pdfIn PDF document text
    • https://legacyltg.com/wp-content/plugins/super-forms/uploads/php/files/731c2186a46c146dc9928822ea556e22/8667804216.pdfIn PDF document text
    • https://www.mybizwebsites.com/wp-content/plugins/formcraft/file-upload/server/content/files/160904590c8a46---xijano.pdfIn PDF document text
    • http://marsalanoleggio.it/userfiles/files/40434333021.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=kanda+sashti+kavasam+in+tamil+pdf+free+downloadPDF 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_off0000c6db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6DB 11000 bytes
SHA-256: 2f73dcdd0bb1b0df4ec0ee732412b0405b5770700877ee953f4ffcbb56873620
font_01_sfnt_off0000e036.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE036 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f848.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF848 24240 bytes
SHA-256: e55401df6a45d61195128f3d11cc6ac617c7b93c39a22a609ed169019d144671