Malicious PDF — malware analysis report

Static analysis result for SHA-256 c9ff4cc79d776d5a…

MALICIOUS

PDF

151.4 KB Created: 2021-07-17 19:58:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8f6cc52078e53f8673be3cd3b7f4137c SHA-1: b72e6d2035d04c4e43c7b44187e79d610a21d2e1 SHA-256: c9ff4cc79d776d5a0fd826ef7884d7608cd1e46141267cd05b8df3f1aa6d3bab
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many pointing to domains that appear to be compromised or disposable, suggesting a link farm for SEO manipulation or phishing. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to distributing further malware or leading users to malicious sites. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9781

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 http://carefirstwalkathon.com/clients/8/89/89514deb4c0e8807eb046cac28c4977f/File/nilimuxagozogas.pdf
    • https://sokolzgierz.pl/web/uploads/files/21776422253.pdf
    • https://3dreamvr.com/wp-content/plugins/super-forms/uploads/php/files/785758d444a85f92275d13d2b8dfb27a/netafipefejotadepilanezus.pdf
    • http://edwindijk.nl/home/edijk/domains/edwindijk.nl/public_html/uploads/file/24722871515.pdf
    • http://urgentcarepb.net/userfiles/file/julana.pdf
    • https://www.hamburgeriaagricola.com/wp-content/plugins/super-forms/uploads/php/files/rv311l9mfjjaqobr7lkoo924sp/jujalurepugarukom.pdf
    • https://www.beewellrx.com/wp-content/plugins/super-forms/uploads/php/files/tmp/23294379079.pdf
    • https://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/fb90cb1f7e0d4f77694926bdbeffafba/54080259953.pdf
    • https://www.uniqueartzz.com/wp-content/plugins/super-forms/uploads/php/files/tjfb3r6ulepjdrh6tidl3o87ud/36798190770.pdf
    • https://kicksomeglass.com/wp-content/plugins/super-forms/uploads/php/files/8ea5bb2f7a8b3773dd00f5f1ce06a4f3/95833249193.pdf
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606d1ae4bc16d---datamimuregofom.pdf
    • http://www.kzhep.in.ua/wp-content/plugins/super-forms/uploads/php/files/krva9rht3302eo887nqe4ptc26/4277637901.pdf
    • http://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078625e883ab---19731657736.pdf
    • http://pferdefreunde-brueckenhof.de/sites/default/files/userfiles/file/dilivota.pdf
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a6a3b52c668---25918149210.pdf
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/e3e896f656e3c17454c17ef8a77d47d3/21580844090.pdf
    • http://sp3siemianowice.pl/userFiles/files/35560393129.pdf
    • http://mazdooradda.com/userfiles/file/gewadek.pdf
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16085311305703---nonewopusidesazomik.pdf
    • http://topenglish.sk/app/webroot/gallery/files/5487972519.pdf
    • http://sanarina.de/ckfinder/userfiles/files/sidenotapusesida.pdf
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088ebdddcc66---durixumajimugitin.pdf
    • http://vilaportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cba81bdc01a---51430174840.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=quantum+theory+of+light+was+given+by
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001c651.bin
9ea9197b6a75c7fe67a727ea228f5add925cef9a7182c4c37535d81b948c8910
pdf-font-stream PDF embedded font (sfnt) at offset 0x1C651 16108 bytes
font_01_sfnt_off0001db87.bin
055067ff83afa7d0b35ca654742614819a8f36ebecb962163de8bcb326bc013b
pdf-font-stream PDF embedded font (sfnt) at offset 0x1DB87 11224 bytes
font_02_sfnt_off0001f5c8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1F5C8 16792 bytes
font_03_sfnt_off00020dda.bin
ec9d92680eb071cdece1a58acd249a101369c1a88f40b7a1f4f02d9d8fb5fd66
pdf-font-stream PDF embedded font (sfnt) at offset 0x20DDA 24448 bytes