Malicious PDF — malware analysis report

Static analysis result for SHA-256 16fc5d77f42361ea…

MALICIOUS

PDF

92.6 KB Created: 2021-07-02 12:10:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 104b63fad0e5849f72dc3a52ac1441ad SHA-1: c455d42163455257ef22b6c24915d23a1fa17282 SHA-256: 16fc5d77f42361ea7598ce74193767ebe658fbf8ce680589c675d33e7410f741
164 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is unreadable, but the heuristic firings and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 7

  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://philabc.ru/uplcv?utm_term=sciatica+pain+for+months
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/cf370acd33329f4beae3cbbc405b2604/86237396656.pdf
    • https://angkoronetour.com/userfiles/file/bezizaxe.pdf
    • https://vildmarksjagt.dk/userfiles/file/15156282819.pdf
    • http://dlt-nkp.com/fileupload//file/39625576137.pdf
    • http://euro-ex.com/images/blog//file/wapebinapasimate.pdf
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099f5398e560---53618772883.pdf
    • https://www.karavanlakesfet.com/wp-content/plugins/super-forms/uploads/php/files/53c93397c3b20449ea7655228c81d8df/30543776800.pdf
    • http://africansafaris-spain.com/FCKeditor/editor/filemanager/connectors/php/connector.php?Command=FileUpload&Type=File&CurrentFolder=%2Ffile/perajexuxasoluxapileb.pdf
    • https://www.sudburyhighspeedinternet.ca/wp-content/plugins/super-forms/uploads/php/files/fd1b195d75f9edf3944474ac7fe8c272/18211318038.pdf
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bb7d8dd7063---joganarok.pdf
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160bf9e6caad9f---gapejevivupolekopiwoxunuf.pdf
    • http://www.everhouse.lt/wp-content/plugins/formcraft/file-upload/server/content/files/160b9c4bea6ff3---jaruwoguzim.pdf
    • http://www.canadavisaservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a14df5b2536---xaxalevofukowitigi.pdf
    • http://xboxheerlen.nl/userfiles/file/19064987457.pdf
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/160ba87cc8730f---bixokivogom.pdf
    • https://hopefor.today/wp-content/plugins/super-forms/uploads/php/files/6a0269828cf40ff181f1745c8a5b9589/zukixuxorasujuvupovoba.pdf
    • https://www.marvistasales.com/wp-content/plugins/super-forms/uploads/php/files/f74c1080c97f5904b0188ec78aa28753/42937720384.pdf
    • https://fieldofgreen.com/wp-content/plugins/super-forms/uploads/php/files/36706ba3801d847e0d9d555edf2f49ac/98771702799.pdf
    • https://asaptransfers.co.uk/wp-content/plugins/super-forms/uploads/php/files/bl3m2rin2fgpoqldgi98q32374/mekujoladigoxu.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085d335efeaf---87593097158.pdf
    • http://www.haztartasigepszakuzlet.hu/pics/file/rokinojapamabivamagi.pdf
    • http://jhsclassof63.com/clients/c/c8/c8cc7cee7579ddcd469b669c0eb172d8/File/13185674114.pdf
    • http://valdhans.cz/userfiles/file/70399587329.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_off000106f7.bin
7b6d48919bde821939a96769e50929950f02c2a2adbaf30969a4538243671fdd
pdf-font-stream PDF embedded font (sfnt) at offset 0x106F7 10640 bytes
font_01_sfnt_off00011f1a.bin
344a1ea6047e79e5f8f2d73588d0b12afebb7f3e5c0541fb1417cc906ee2c01e
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F1A 16972 bytes
font_02_sfnt_off00014b91.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14B91 16792 bytes