Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b54c55c6a429f99…

MALICIOUS

PDF

94.3 KB Created: 2021-07-08 03:52:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: e47f63bc82d36e01f7eaaa680f71e53c SHA-1: a1577a2484469ad0ea935aa84e8b0c59b52188d5 SHA-256: 3b54c55c6a429f99ba6f53a5b875aa26c7ac63c4a92fa0196a83c989918b2fd1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised WordPress installations or disposable domains, indicating a link farm or phishing lure. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for distributing further malware or conducting phishing attacks. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document, potentially leveraging embedded JavaScript for malicious actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

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://synerhu.ru/uplcv?utm_term=mechanical+engineering+interview+questions+and+answers+book+pdf PDF link annotation
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/990gtv6v4it28ggg4tb7janis1/bazufo.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b44158320d4---kixofel.pdfIn PDF document text
    • http://alibabashipping.com/userfiles/file/47246959024.pdfIn PDF document text
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ade25a49562---famixixufovoviga.pdfIn PDF document text
    • http://lungshingcentre.com/userfiles/niketemezolalif.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/rudaza.pdfIn PDF document text
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c32981f1739---21242447420.pdfIn PDF document text
    • http://www.alfapilates.pl/upload/file/32493175487.pdfIn PDF document text
    • http://lindseyderence.com/userfiles/files/94256895850.pdfIn PDF document text
    • http://brickform.cz/obrazky/files/61704706710.pdfIn PDF document text
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/21500781133ae23c8248d4b0b212bcf9/87511867957.pdfIn PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/k9elhhkioob12mqed7kuir850n/bedomoxubar.pdfIn PDF document text
    • http://kotolantopeni.cz/file/peteko.pdfIn PDF document text
    • https://transcendenceit.com/wp-content/plugins/super-forms/uploads/php/files/44a6ab65c23ea2df268dbba5953ed7a7/79115777557.pdfIn PDF document text
    • http://midiabyz.com/wp-content/plugins/super-forms/uploads/php/files/3a253326a317e91d071d532d1d5584ec/82327589111.pdfIn PDF document text
    • http://www.supercarrentalsofmiami.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097f6b084d2f---30796362594.pdfIn PDF document text
    • https://www.hungryalex.com/wp-content/plugins/super-forms/uploads/php/files/6m6oank56ntnj6h7oth4pv4tq4/83233194132.pdfIn PDF document text
    • https://dipinkrishna.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071a0e992cb9---72079379245.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/20ae6c46309c5080e3422796a4c59109/mamolarimebojuputepoloza.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/140b418e25bdc2f991bdfcae74250913/90437688538.pdfIn PDF document text
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/16082687befdd3---22193969386.pdfIn PDF document text
    • http://anthonyellisonfamilyreunion.com/clients/f/ff/ff850d76676c1858bf5e443b7a907d3b/File/88165697929.pdfIn PDF document text
    • https://jordan.si/dokumenti/file/kesitoto.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609badf8b4d2e---lezigegamalibixagidi.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010a0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A0B 17636 bytes
SHA-256: aa821a3da4a716954fca90f4dcc473d1404a030ac9ab9a5c2a2e3943b4418e6e
font_01_sfnt_off00013880.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13880 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00015097.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15097 11524 bytes
SHA-256: a3a65f33fa9c4602ee16d2ac31cd0df3488e4b054bca64fd5aaf26ce07f20707