Malicious PDF — malware analysis report

Static analysis result for SHA-256 f0233804cb6282a6…

MALICIOUS

PDF

82.8 KB Created: 2021-09-11 01:28:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 1f3c9a8386e939a5fbc3bcb1804776dc SHA-1: 66b4d6186cd661304e452932e184a31f1be3a9c3 SHA-256: f0233804cb6282a603e92c2abdde8f5359635833219c4d97b717b3f49db72923
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. Additionally, the document acts as a link farm, directing users to multiple external URLs, some of which are hosted on compromised CMS uploads. This suggests an attempt to lure users to malicious sites for phishing or to download further malware. The ClamAV detection and ML classifier further support its malicious nature.

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
  • 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://oniceh.ru/uplcv?utm_term=best+japanese+keyboard+for+android PDF link annotation
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b2d26cb5c3---21487579058.pdfIn PDF document text
    • https://fleuriste79.fr/ckfinder/userfiles/files/82015385013.pdfIn PDF document text
    • http://mybyblos.com/userfiles/file/50710553643.pdfIn PDF document text
    • https://vozilasavozacem.rs/files/dizowiv.pdfIn PDF document text
    • http://mixline.ru/img/lib/file/76154475415.pdfIn PDF document text
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/6sh4p3cs61tce2uicri85roloc/49049051519.pdfIn PDF document text
    • https://www.isgs.org/wp-content/plugins/super-forms/uploads/php/files/032c7ae99cde64db1dd8a7e76a239e21/vugawaboliki.pdfIn PDF document text
    • https://www.nhabe.com.vn/ckfinder/userfiles/files/defogilaralo.pdfIn PDF document text
    • https://motoquadro.de/userfiles/file/pomawivobo.pdfIn PDF document text
    • https://tradingphrases.com/userfiles/files/bepexukow.pdfIn PDF document text
    • https://10kshot.com/customerinterview/ckfinder/userfiles/files/906943107.pdfIn PDF document text
    • https://grancom.by/upload/docs/19212448075.pdfIn PDF document text
    • http://inggeo.eu/userfiles/files/37615915303.pdfIn PDF document text
    • http://almawred-sy.com/files/adminfiles/files/moraxorurozipuvifi.pdfIn PDF document text
    • https://abouelhoulgroup.com/userfiles/files/57876251929.pdfIn PDF document text
    • http://burragebrothers.org/demo/jolie/beta/userfiles/files/66237930327.pdfIn PDF document text
    • http://thriftstorewebsites.net/flash/thriftstorewebsites.net/file/bivuna.pdfIn PDF document text
    • https://strategieb2b.ca/userfiles/file/puvasobevowu.pdfIn PDF document text
    • http://gewidor-gmbh.de/uploads/files/57983338516.pdfIn PDF document text
    • http://hefei.chinatupai.com/web/js/ckfinder/userfiles/files/47840071775.pdfIn PDF document text
    • http://birdwatching.sk/media/file/gabevejokunenevijowakudir.pdfIn PDF document text
    • http://midospa.com/upload/files/54249365487.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_off0000db50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB50 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f362.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF362 18856 bytes
SHA-256: 973fc5f19e978aeeeb298f93e25ef0f1d9b8da3fc3f1f23cc6ceaf386c43bdc0
font_02_sfnt_off00012443.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12443 10976 bytes
SHA-256: 9b7a20695d45f1449f2429bc1b561c2d2b83f65fae60534b907e3403c64414e6