Malicious PDF — malware analysis report

Static analysis result for SHA-256 6f44624812a1f110…

MALICIOUS

PDF

90.4 KB Created: 2021-06-27 10:47:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9d6b6e8fefd2efe6f8da31c469d8577c SHA-1: 4de9ad93c5496ea173cba204db1784794cf42a12 SHA-256: 6f44624812a1f110b5c317b2139f5f5e91401213467e6a8c3e8bb6955bc656e6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a link farm, with many URLs pointing to external sites, some of which are hosted on compromised WordPress installations. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. No scripts were extracted, and the document body was unreadable, so the primary attack vector is the collection of external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

Heuristics 6

  • 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.
  • 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://chmelo.hu/sites/default/files/file/puvof.pdf
    • http://agnieszkapawlik.com/userfiles/file/tevibopelotewenu.pdf
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/c07426150a2e1758c8dbe89037cbe362/vatapexonaxarerevo.pdf
    • http://goref.ru/files/file/70173452297.pdf
    • https://loyallcanada.ca/editor_files/file/xukimoxisuvaloj.pdf
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/a4da16c28a6c39025b3aacfdc4f6ca12/492517312.pdf
    • http://angeladaniel.eu/uploads/files/83626170107.pdf
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a11baf48d36---ziregan.pdf
    • https://ecoinkworld.com/wp-content/plugins/super-forms/uploads/php/files/5d5d44746504c4129948f1a74f035813/63114173871.pdf
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160727e702bebb---94589189264.pdf
    • http://lamekatus.ee/uploads/ckeditor/files/fefemigikirudedakuz.pdf
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/n4oj8js7sdc4grr25ai04r9dv4/26186388049.pdf
    • https://slavica.ru/wp-content/plugins/super-forms/uploads/php/files/aa34f01a07a5c55808640862da11af14/18295239729.pdf
    • https://nailseasupportgroup.com/wp-content/plugins/super-forms/uploads/php/files/ed89cf45ca73a0d147fe1d78b86e8d9a/24686270175.pdf
    • http://atut-biuro.com/uploaded/file/salapikuka.pdf
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/4df5287ef0c4d7ef74f8050f9f7379d4/jitezemifepupikoxaz.pdf
    • https://asiquim.com/ckfinder/userfiles/files/17836055313.pdf
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16088615c6d118---tuzoxejaviworupiwevorin.pdf
    • http://jatyn.cn/upfiles/202106/file/1622538188.pdf
    • http://www.photobreak.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16070cc224418e---mebogamefedunarivoj.pdf
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bc40df430a5---dasevovoloki.pdf
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609ab04c397f5---44746056063.pdf
    • https://www.icslights.com/wp-content/plugins/super-forms/uploads/php/files/384a2bb9172ae3aa00e6793c00e5b90a/vibabasasiwukidevekugez.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=happy+2nd+anniversary+sister
    • 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://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ff81.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF81 16792 bytes
font_01_sfnt_off00011793.bin
111db620b29097de9e076a43fe85c12887e698f416c72f77a4f69adc853eeb84
pdf-font-stream PDF embedded font (sfnt) at offset 0x11793 17204 bytes
font_02_sfnt_off000142bf.bin
8cdc4ad2c7d95dd4942235ba5807b398c2586b31b2f2c84773cb0dcdd9f76f24
pdf-font-stream PDF embedded font (sfnt) at offset 0x142BF 10508 bytes