Malicious PDF — malware analysis report

Static analysis result for SHA-256 23ef9e55763c8003…

MALICIOUS

PDF

78.7 KB Created: 2021-09-03 02:09:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 5fe83f875219560a5b89bbad45d221a2 SHA-1: e5c4daf4a9c5ee05536a119b7b72d03091f2b292 SHA-256: 23ef9e55763c80031a2f42d93cfca10557ddb0d0c988f32bcdf8042db67f9c6c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of links, many pointing to compromised WordPress sites and disposable hosting, suggesting a link farm designed to distribute malicious content or phish users. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware delivery via these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://project-lovcen.me/userfiles/file/zusizawek.pdf In PDF document text
    • http://dztechfin.com/upload/file///38226595434.pdfIn PDF document text
    • http://happyhanool.com/ckupload/files/zazunuduve.pdfIn PDF document text
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/160bd69f62f594---sovitapivajevexalodow.pdfIn PDF document text
    • http://omni-links.com/images/blog/file/71565469897.pdfIn PDF document text
    • https://mikepromedia.com/wp-content/plugins/super-forms/uploads/php/files/ns2v6e1n558r771c0naplrldn0/puropovosojek.pdfIn PDF document text
    • https://www.willmarareachamber.com/ckfinder/userfiles/files/24518937129.pdfIn PDF document text
    • http://sunwisechem.com/Uploadfiles/files/31160311592.pdfIn PDF document text
    • https://www.businesswatchguardingservices.co.uk/wp-content/plugins/super-forms/uploads/php/files/r55jq2gagnqojbn45mniqg0h42/remewekana.pdfIn PDF document text
    • https://rockyshairsalon.com/wp-content/plugins/super-forms/uploads/php/files/qhhiaecom3n8qgqt8i9q9diird/99338416258.pdfIn PDF document text
    • https://signaturetowerpune.com/wp-content/plugins/super-forms/uploads/php/files/2bli3uger6aejkr54k28f043b7/21135455050.pdfIn PDF document text
    • https://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/u01fvdvn5ea42upuaj2f54f2l5/golugikixewid.pdfIn PDF document text
    • http://les-dvorik.ru/userfiles/file/xejejazepesatavi.pdfIn PDF document text
    • https://teenvolunteerhouston.com/wp-content/plugins/super-forms/uploads/php/files/daeabd880cdef4520b7437039f0c6c26/dutabijob.pdfIn PDF document text
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606da5cee75cb---mumidak.pdfIn PDF document text
    • https://artsketch.ru/wp-content/plugins/super-forms/uploads/php/files/9889c0607ec6535e33fa4861bbcfb7e1/39690864886.pdfIn PDF document text
    • http://sterkrade.net/ckfinder/userfiles/files/dagefuxuketagibaki.pdfIn PDF document text
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/16095e1896e102---puxenimudebotewibirafo.pdfIn PDF document text
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/161091f3d9af2a---46906468027.pdfIn PDF document text
    • http://blankheich.de/images/uploads/file/jixotobugeretuwufapapoxew.pdfIn PDF document text
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/16097ba8dc0f49---49664933064.pdfIn PDF document text
    • https://mintowncoffee.net/uploads/images/files/sagibajinarog.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/8qfdvvqnorbj59cm830kdnh8l1/13299797126.pdfIn PDF document text
    • http://fixmyhelicopter.com/project-new/christianbook/upload_images/file/bifewiresobiwitemoduvi.pdfIn PDF document text
    • https://theatresaucinema.fr/uploads/file/jovap.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=alkylation+of+enamines+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_off0000cfcb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFCB 10744 bytes
SHA-256: 8f59a79656d6fdf5c1b24c74881e278fd7a4a04d2337a3979e2624c5c88cfa46
font_01_sfnt_off0000e888.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE888 17180 bytes
SHA-256: 5cdf7e350eaa02cf512f68c15d0c640b0204071793e1092d6df7e1e50e5608ee
font_02_sfnt_off0001150f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1150F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1