Malicious PDF — malware analysis report

Static analysis result for SHA-256 dbf1f6f9dfa4b069…

MALICIOUS

PDF

86.9 KB Created: 2021-07-06 23:11:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0fd4555272d027293e4ab91c596669ec SHA-1: 5b44140925ef7377120daa88728038aa8a8b56f3 SHA-256: dbf1f6f9dfa4b06986eda2a4e4324f3adb1d98e930bdeaa79776b688e0004134
156 Risk Score

Malware Insights

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

The PDF contains a link farm directing users to multiple URLs, many of which are hosted on compromised WordPress sites using formcraft or super-forms plugins. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The document body is unreadable, but the heuristic firings clearly point to a link farm designed to lead users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160ac492a7616f---31456802600.pdf
    • https://samudra99.com/contents//files/5813375126.pdf
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/mq0b3ov6fjk8ekkgvb9lqguj17/tekonud.pdf
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/160d77679dfb99---puvikirowovepewadeji.pdf
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/0d3395fbbc614975fb2aeb2e8d4394a9/siriteliwamivubuzakib.pdf
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/b915ac029135fcf10b2e91797025f9ee/dokepori.pdf
    • http://cageart.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608381e7e4d43---rimugagegupoko.pdf
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc97ebb350---namuvokutewukoluxer.pdf
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/js430i7ffmbfg5bgnefb37jn36/jamutifub.pdf
    • http://pphu-joanna.pl/fckpliki/file/tolidefugifuvera.pdf
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b59c336c65b---kesirelugu.pdf
    • https://bf-pomosch.ru/wp-content/plugins/super-forms/uploads/php/files/mr178ive24pfi22vnqn7dfhqn7/79001551954.pdf
    • https://www.adelaarenergy.com/wp-content/plugins/super-forms/uploads/php/files/c9aofnofql87ltaio0hadrds6d/riwedope.pdf
    • https://loskutova.site/wp-content/plugins/super-forms/uploads/php/files/d5d12bc93074b6d56775a62e74c84af7/82991032242.pdf
    • http://phuquytravel.com/nguyenvanlinh/files/nijeseletudumawo.pdf
    • https://fokusmedia.com/images/uploads/34191594336.pdf
    • https://cosalesrep.com/wp-content/plugins/super-forms/uploads/php/files/50cc6f6bd3027ab3bc2ba1f665ceba4b/26928638903.pdf
    • http://www.yoko-ono.be/images/userfiles/file/jadisusivukaketuzufajuv.pdf
    • http://rungrawin-itt.com/userfiles/files/12378973991.pdf
    • https://floridainvestment.cz/files/file/85654954846.pdf
    • http://adoriantarla.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16084aaedeb5c5---25362652870.pdf
    • https://www.arphplumbing.co.uk/wp-content/plugins/super-forms/uploads/php/files/kqldell968fd0qcui55tj9eer4/64826575782.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=store+capital+stock
    • 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_off0000f240.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF240 16792 bytes
font_01_sfnt_off00010a52.bin
8b57e8883f0de58fd6ea5c5f500625a2cc48492a2dc9fee75e5f12e3b58e9d7c
pdf-font-stream PDF embedded font (sfnt) at offset 0x10A52 17108 bytes
font_02_sfnt_off000136b4.bin
14838e45d007298dc09a96cc1d5961fef799451922835d5ba1935d1d8c39132e
pdf-font-stream PDF embedded font (sfnt) at offset 0x136B4 10432 bytes