Malicious PDF — malware analysis report

Static analysis result for SHA-256 753831bd5e55a654…

MALICIOUS

PDF

79.1 KB Created: 2021-09-17 06:52:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 069bd476cb7849ed4f19168d73e64aa8 SHA-1: 7b7da00db71d030ac75de2cc15f108085e5d326e SHA-256: 753831bd5e55a654de6cb4da252151339f7fbf6c0879fd0e9704c3f9f51e7ee4
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which are hosted on disposable domains and appear to be part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery. The presence of embedded JavaScript suggests an attempt to execute malicious code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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 http://weiddy.com/uploads/files/202109090619392249.pdf In PDF document text
    • https://moraure.net/js/ckfinder/userfiles/files/levovadag.pdfIn PDF document text
    • http://michalpavlicek.com/uploaded/file/12188411110.pdfIn PDF document text
    • https://cvssteelex.com/ckfinder/userfiles/files/jasezunowamijujaj.pdfIn PDF document text
    • http://volvo-cars.jp/js/upload/files/59794697752.pdfIn PDF document text
    • http://logiccpacma.com/ckfinder/userfiles/files/xamutetinulumovez.pdfIn PDF document text
    • http://bk-plus.at/userfiles/files/zokom.pdfIn PDF document text
    • http://grandviewgroupresort.com/upload/files/xojuwuraveg.pdfIn PDF document text
    • https://binhvi.com/upload/files/63468727685.pdfIn PDF document text
    • http://hcstonetw.com/uploads/files/202109111648005794.pdfIn PDF document text
    • https://jahanchart.ir/data/files/file/morotetuga.pdfIn PDF document text
    • http://borisovhlebprom.by/var/upload/file/47584860945.pdfIn PDF document text
    • http://iltorg.ru/upload/file/bevez.pdfIn PDF document text
    • https://myclubowners.com/userfiles/files/rugaxiviporujaliduxit.pdfIn PDF document text
    • http://loadcell.vn/Images_upload/files/83252149650.pdfIn PDF document text
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613b5af5ce01b---joverogukasufabare.pdfIn PDF document text
    • https://sassanoproperties.com/FCKeditor/file/64506410214.pdfIn PDF document text
    • https://bomberosdenavarra.com/userfiles_nexo/files/57591049379.pdfIn PDF document text
    • http://flemingdecal.com/uploads/assets/file/desusibafubesifimata.pdfIn PDF document text
    • http://www.naraihillgolf.com/admin/userfiles/file/29822652685.pdfIn PDF document text
    • http://tunesistudio.eu/userfiles/files/33637151497.pdfIn PDF document text
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613167313a603---56652090186.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=backup+apk+and+data+without+rootPDF link annotation
    • 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_off0000cfc4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFC4 10596 bytes
SHA-256: dc724589feecc5b15d5e005f1b37f5c404e4ac68050fe3df92fc8fc3be5a9722
font_01_sfnt_off0000e806.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE806 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010018.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10018 18260 bytes
SHA-256: 8123623cd26416564271c1b766d0865fa23652be756b9df7860fa980dde2750f