Malicious PDF — malware analysis report

Static analysis result for SHA-256 77348a49894bef93…

MALICIOUS

PDF

133.4 KB Created: 2021-09-17 20:10:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: bc10de7b529f18fe15f00defdabbe699 SHA-1: f2c558325d1e235eba88b652b02d43ac0b4ff434 SHA-256: 77348a49894bef9337aaa2dbcae0852ab23eabc3c8841bcf12b33aecce4dc22e
164 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as a phishing trojan and by an ML classifier. It contains embedded JavaScript, which is often used to exploit PDF vulnerabilities or redirect users. The document also features a large number of external links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to distribute malicious content or phish users. The presence of embedded JavaScript indicates an attempt to execute code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9768

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 https://synerhu.ru/uplcv?utm_term=ministry+of+magic+location PDF link annotation
    • http://tyextractor.com/d/files/21288845492.pdfIn PDF document text
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/407d15de6994aa788f5be64d3f337cb9/xuzeri.pdfIn PDF document text
    • http://easy-sleep24.de/shop/images/editorfiles/file/37215088023.pdfIn PDF document text
    • http://cathyourhair.nl/js/ckfinder/userfiles/files/lupanuvisokipenu.pdfIn PDF document text
    • http://vinhthuan.com/upload/files/sutuwokabolip.pdfIn PDF document text
    • https://lacgl.org/upload/editor/file/lumedoja.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613ba8f50df92---napozewubewovimazunokug.pdfIn PDF document text
    • http://ke-sen.com/userfiles/file/1631686559.pdfIn PDF document text
    • http://3e-recycling.ru/app/webroot/filesfiles/vedesowovuwe.pdfIn PDF document text
    • http://autodilykanka.cz/cmsimple/images/file/ligimigowapumolamutomi.pdfIn PDF document text
    • https://shop-ecobati.com/medias/upload/files/birometabemifinowodokad.pdfIn PDF document text
    • http://glassick.com/userfiles/file/94594151606.pdfIn PDF document text
    • http://infas.cz/images/wiswig/file/gewavezivufidugemizada.pdfIn PDF document text
    • https://giant-nano.com/app/webroot/userfiles/files/tarijadipabazubekasese.pdfIn PDF document text
    • http://pebyte.com/wp-content/plugins/super-forms/uploads/php/files/co2rgmukoarjs64k60fa7f7f44/50908860060.pdfIn PDF document text
    • http://onestep-tokyo.com/userfiles/file/zomajaxuxeta.pdfIn PDF document text
    • http://gfb.it/upload/fck/file/54424865790.pdfIn PDF document text
    • https://ivanamihic.com/files/22465352741.pdfIn PDF document text
    • http://espressobuilders.com/app/webroot/files/userfiles/files/xezekesegisutevulutazi.pdfIn PDF document text
    • http://scenekunstskolen-efteruddannelsen.dk/ckfinder/userfiles/files/90299810821.pdfIn PDF document text
    • http://xsjsbzrw.com/uploads/files/14578787169.pdfIn PDF document text
    • https://gionggiacam.com/ckfinder/userfiles/files/junot.pdfIn PDF document text
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/161373b912d498---13373001634.pdfIn PDF document text
    • http://iproperty.ae/userfiles/file/1230510565.pdfIn PDF document text
    • http://volkshilfe-vlbg.at/images/content/files/6342804170.pdfIn PDF document text
    • https://mountainbrookbuilders.com/home/mountain/public_html/ckfinder/userfiles/files/dametaleduwodusofumateju.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_off0001a692.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A692 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001bea9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1BEA9 10656 bytes
SHA-256: b3b4dab72da74e161f6a0f3daabec5f749194989ca8cfb8a48671232ef188a76
font_02_sfnt_off0001d71b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1D71B 18472 bytes
SHA-256: 8b5329f9a5d7b4c3d55a06d4a58a83e53d8e09cabc93b6b626968dd40c3289c5