Malicious PDF — malware analysis report

Static analysis result for SHA-256 59d91c269fc5db4d…

MALICIOUS

PDF

72.3 KB Created: 2021-09-06 19:32:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 494859ead27350834ea001c6773a87fe SHA-1: 28cc94afe32015930271bf53f5a4806f21b3d29e SHA-256: 59d91c269fc5db4d182a498871ffc57e26bd6618a6db59a5b6ea14113aca64bb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm with numerous URLs pointing to various domains, many of which are hosted on compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the structure and URL patterns are consistent with malicious PDFs designed to redirect users to harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://inwebjor.ru/uplcv?utm_term=practical+knowledge+of+steam+boilers+pdf
    • https://sonarmusic.hu/up_image/file/74232889082.pdf
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acb528a40ad---62567943327.pdf
    • https://earplighting.com/wp-content/plugins/super-forms/uploads/php/files/f9579cf6b4856fc30cd4e366d20b8d82/30660281081.pdf
    • https://tskrea.com/userfiles/file/suliniwokuv.pdf
    • http://lahma.pl/_u/userfiles/file/mowiverogutixewifat.pdf
    • http://ersatzmonitor.de/userfiles/file/zizulopamiluv.pdf
    • https://ahreco.com/uploads/news_file/34123599999.pdf
    • http://gpba.ge/admin/ckeditor/ckfinder/userfiles/files/94030105151.pdf
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/9275dacff1b68b34492eda04a115f6dc/56917848489.pdf
    • https://vernadoc.com/wp-content/plugins/super-forms/uploads/php/files/0c8140fd79e004ca98bf1aec822765b4/40386633405.pdf
    • http://jaqalsports.com/files/file/vabemaxoxuti.pdf
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/6050aa40ca849fe1ef9f29c2d4f65f60/jimeluxomekusuregoxajusu.pdf
    • https://gbagencement.fr/uploads/file/59414977862.pdf
    • http://scherzerpc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/61607420541.pdf
    • https://saraelv.no/wp-content/plugins/formcraft/file-upload/server/content/files/160c2a9991cbf1---vamimexukafojawaba.pdf
    • http://f-okinawa.com/img/tmp/file/punelogizefozasedi.pdf
    • https://www.adelaarenergy.com/wp-content/plugins/super-forms/uploads/php/files/u68d5r474jtnl8al20lktrp734/fotuputetotanuxapax.pdf
    • http://raylutickenterprises.com/userfiles/files/69744457668.pdf
    • http://imcborivali.org/userfiles/file/misepilebikasorupux.pdf
    • http://holidayservicemarsala.it/userfiles/files/50185405458.pdf
    • https://mobile-translator.eu/app/webroot/media/files/badazugewivawugu.pdf
    • http://noithatdangcap.vn/app/webroot/uploads/files/27104329273.pdf
    • http://app8itebarandgrill.com/admin/images/file/fekejosetesopaliti.pdf
    • 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_off0000b854.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB854 16792 bytes
font_01_sfnt_off0000d06b.bin
ae0bec0e9e7d4a488c3d3ada521fd68f2a1fc164d888c1d507669788ef52a7a5
pdf-font-stream PDF embedded font (sfnt) at offset 0xD06B 11280 bytes
font_02_sfnt_off0000ea82.bin
c02bd787c568451c91232776341a1b84a437f8c15a954c5c791a8cdc491cc3a4
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA82 15536 bytes