Malicious PDF — malware analysis report

Static analysis result for SHA-256 617a6431d89598b2…

MALICIOUS

PDF

73.3 KB Created: 2021-05-09 06:35:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0957f604a4b8db931c09d66e1a5e1b45 SHA-1: 35d4044d3f000b3aa5d193ed423b3e31344847bf SHA-256: 617a6431d89598b21e63d1c75af5c838c0b8203f7e2f6b1d0dbda36259cbeec0
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF document contains heuristics indicating it is a link farm and a browser extension installation lure. ClamAV detection and ML classification strongly suggest malicious intent, likely phishing or malware delivery. While no scripts were directly extracted, the document's structure and embedded URLs point towards a social engineering attack aiming to trick users into downloading further malicious content or providing credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074461e5a0ac---16521761205.pdf
    • http://www.realisthotel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160853b5ec016d---1560344874.pdf
    • https://amerismithenterprises.com/wp-content/plugins/super-forms/uploads/php/files/e147e3d286a0f687cb35e1d4366c10f0/koperepeju.pdf
    • https://studio45.live/wp-content/plugins/super-forms/uploads/php/files/eo8m6ql3u0ba4hamgfvrkjjudj/29260002398.pdf
    • http://www.next-conseil.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607580759d859---48933835558.pdf
    • https://bellevuecommunityfoodbank.org/wp-content/plugins/super-forms/uploads/php/files/1fa02a9a2fa49c62e1b8cb06dfa164ab/venimujoregixigezubapini.pdf
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607943c9c0160---19492269022.pdf
    • https://robinio.de/wp-content/plugins/super-forms/uploads/php/files/hq5qti8kro4fjkhq1gvp9fu520/mizikofixe.pdf
    • https://benjamindreyer.com/wp-content/plugins/super-forms/uploads/php/files/413d51e51d0810113002a75db6c45b2f/beruzexegazovufafununa.pdf
    • https://baodinhsolar.com/wp-content/plugins/super-forms/uploads/php/files/9hifhknnaoud49vk94um34s1hh/27367951216.pdf
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160860cbf43e26---88602726273.pdf
    • https://tirthmobile.com/wp-content/plugins/super-forms/uploads/php/files/8u237k1g9dtg3v9sg1gg5jqd2n/60669875602.pdf
    • https://www.helmmsp.ca/wp-content/plugins/super-forms/uploads/php/files/00851a410ac9e52de31cc7bff2a86c95/27961536610.pdf
    • https://aawyx.com/sites/default/imageuser/file/17697965152.pdf
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073ed54aa86d---vanawijog.pdf
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/d91a7615119bdbeecc9021b07f46678a/vokavenabalo.pdf
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607bdb708ace6---kosugibap.pdf
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160856097240a6---46811141166.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=yahoo+finance+app+for+ipad
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e32c.bin
84cef31707236540d27764b74f3443e98fd0073670d46fb5dd52b3e246bf70d9
pdf-font-stream PDF embedded font (sfnt) at offset 0xE32C 4992 bytes
font_01_sfnt_off0000f425.bin
8efeaea79f85c11bbe8f31182d55c59d82cffdadb135afbf9ddf9f808bc037a2
pdf-font-stream PDF embedded font (sfnt) at offset 0xF425 10584 bytes