Malicious PDF — malware analysis report

Static analysis result for SHA-256 b862ef6742cdbf72…

MALICIOUS

PDF

72.0 KB Created: 2021-09-25 10:44:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f2d5907056cff3afc4231d32fc5b529b SHA-1: dbb96538c6fe01c69b9384075ca7087d480f8083 SHA-256: b862ef6742cdbf72651b56117d4337956a2440f8141ee3113e49685a9c03b98c
204 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and a link farm pointing to compromised WordPress uploads and disposable hosting, indicating an attempt to trick users into downloading malicious files. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. The presence of embedded JavaScript suggests it may be used to facilitate the download or execution of a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • LOLBin token sequence in document text high SE_LOLBIN_RUN_COMMAND
    Extracted document text contains a Windows script/execution tool name (PowerShell, mshta, cmd, rundll32, regsvr32, …) within 220 characters of a dangerous flag, command verb, or URL. This is a visible 'run this' instruction in HTML/PDF/RTF lure bodies, or — in macro-laden Office files — the macro's own string-pool entries appearing adjacent in extracted text.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://divinenine.net/userfiles/file/lusugisisaponukakevevo.pdf
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16148ba47b4712---4425766699.pdf
    • https://nbc.com.vn/ckfinder/userfiles/files/20111990552.pdf
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/16136c9b303b92---52651602906.pdf
    • http://eros-arena.com/eros/userfiles/file/bazobapogapasa.pdf
    • http://hotspot-usa.com/js/upload/files/12231459163.pdf
    • https://solarconsulting.org/wp-content/plugins/super-forms/uploads/php/files/00d6faadb39c8632d3ff76bf2c10dcc6/27338114475.pdf
    • http://csa.china-led.net/static/editor/ckeditor/ckfinder/upfile/files/bemabowanerisesidotokum.pdf
    • https://km2804.com/ckupload/files/dejasipafap.pdf
    • http://arcstema.com/userfiles/files/18447239382.pdf
    • http://ceomit.com/fckupload/file/mowofaruwojevakut.pdf
    • https://www.aironface.com/wp-content/plugins/super-forms/uploads/php/files/1fd0423ca04ac24595d5c98b4f74d22a/44685626129.pdf
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/161303c5a4d1c1---95303756996.pdf
    • http://bbdecontra.com/userfiles/files/misupagamuvoteriseme.pdf
    • https://marblo.com/app/webroot/img/files/6666732431.pdf
    • https://www.libyamonitor.com/sites/all/libraries/ckfinder/userfiles/files/lulujiwukapoxuwikolumu.pdf
    • https://alarrabnews.com/images/content/content/file/85921557902.pdf
    • https://topconta.ro/userfiles/file/80467136020.pdf
    • https://perfecthospital.net/ckfinder/userfiles/files/43177638678.pdf
    • https://magnanelli.com/userfiles/file/70984424613.pdf
    • http://bonsite.nl/phpcmsys/file/gaxuvubukawezoxisopur.pdf
    • http://qdcmd.com/data/files/sevasiresawun.pdf
    • http://wxhsbl.com/ckfinder/userfiles/files/20210920_182251.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=ets2+download+android
    • 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_off0000b639.bin
f8fb4fe57c92eafbe4449236c07915ad8bf24c7bf54d9d36c15822c9afccad84
pdf-font-stream PDF embedded font (sfnt) at offset 0xB639 17760 bytes
font_01_sfnt_off0000e332.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE332 16792 bytes
font_02_sfnt_off0000fb49.bin
cd905543d0125977ba033175c7c161e13d04d5bfd83dc5161c207492fccff794
pdf-font-stream PDF embedded font (sfnt) at offset 0xFB49 10300 bytes