Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1909ae5554b37bc…

MALICIOUS

PDF

79.6 KB Created: 2021-09-09 11:36:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 84b591d904a44792d05895e86b240463 SHA-1: fb4d6698289313cf2e4c5cd24c547bc96ae56fcb SHA-256: a1909ae5554b37bcd025392a0b34977499ca8b0d2cfa392863a28e5af7926333
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many pointing to compromised websites or disposable domains, suggesting a link farm or phishing lure. The presence of external URI heuristics and link farm detections further supports this. No scripts were extracted, but the overall structure indicates a malicious intent to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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 https://philabc.ru/uplcv?utm_term=easy+way+to+root+android+without+pc PDF link annotation
    • http://www.laterveer-biesenbeek.nl/ckfinder/userfiles/files/gikivazamaret.pdfIn PDF document text
    • https://villadorottya.hu/uploads/frontend/files/kigalotuxonuza.pdfIn PDF document text
    • http://turbotechnik24.de/userfiles/file/39814977980.pdfIn PDF document text
    • https://pavaniautismschools.com/wp-content/plugins/super-forms/uploads/php/files/ija9rpuihfr39ptfvcst05qp0h/mivokavazele.pdfIn PDF document text
    • http://lulanjina.net/upload/files/54256457616.pdfIn PDF document text
    • http://drairtools.com/ckfinder/userfiles/files/42972609638.pdfIn PDF document text
    • http://oreade-breche.fr/userfiles/file/17907917328.pdfIn PDF document text
    • http://assushop.com/userfiles/assushop.com/file/42738063682.pdfIn PDF document text
    • https://nabijdefossa.nl/upload/files/46784429495.pdfIn PDF document text
    • http://www.nisbd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130c0693c891---9389511748.pdfIn PDF document text
    • http://zentrumok.com/userfile/files/43102182336.pdfIn PDF document text
    • https://tttinox.com/upload/userfiles/files/91521994651.pdfIn PDF document text
    • http://www.atccs3.it/atccs3/fckeditor/editor/ckfinder/userfiles/files/figiwir.pdfIn PDF document text
    • http://dominopark.pl/public/upload/ckfinder/userfiles/files/kugam.pdfIn PDF document text
    • http://hysansam.com/fckeditor/userfiles/image/96646183485.pdfIn PDF document text
    • http://soluzionebenessere.eu/userfiles/files/28183676910.pdfIn PDF document text
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/d8aac6fdd12608424e2fe294af3f8e10/29702875550.pdfIn PDF document text
    • https://udruga-invalida.hr/files/35688194581.pdfIn PDF document text
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16133e316df490---lodopot.pdfIn PDF document text
    • https://wamsconference.com/wp-content/plugins/super-forms/uploads/php/files/f3b1d5464b346e98b92d8bb928ad7925/67139582215.pdfIn PDF document text
    • https://holcom-solar.com/webroot/img/files/40500500788.pdfIn PDF document text
    • http://osc-pribor.ru/products_pictures/file/raguvitanupopotaridedap.pdfIn PDF document text
    • http://cowmoo.org/ckfinder/userfiles/files/49143973144.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_off0000d2d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2D6 17620 bytes
SHA-256: 9973e3252a8d5e45ddbaf711a7448adc0a9e025248424e2fd23696bd83450430
font_01_sfnt_off00010028.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10028 10716 bytes
SHA-256: 9b836d638a32711dc8de9e435f991cb9e173c125a4efc6c9257036ca5bab9198
font_02_sfnt_off000118cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118CD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1