Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d6e9f9dac2f5d8a…

MALICIOUS

PDF

85.0 KB Created: 2021-09-08 12:58:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1237a4ec57d8f365798f02e66e27b3c1 SHA-1: 39b814861ea828061988028dbfdaeb52d2ad0fd1 SHA-256: 4d6e9f9dac2f5d8ad082039db13672398d86d39c8a4679ec486ffc3e50632124
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains embedded JavaScript, which is often used to exploit PDF vulnerabilities or redirect users. The presence of multiple link farm heuristics and numerous unknown URLs suggests an attempt to obscure the final destination, likely a phishing page or a malware download server. The embedded JavaScript is likely responsible for initiating the redirection or download process.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 http://sun-green.be/ckfinder/userfiles/files/pabade.pdf
    • http://crimesla.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/mibivipilugetuwusuvadil.pdf
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130278740fa7---42363396614.pdf
    • https://narellesastro.com/userfiles/files/musabifilexoxesikolu.pdf
    • http://corporatiegids.nl/uploads/files/rajuz.pdf
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/16133e6047ba0c---gidotonemesokar.pdf
    • http://www.urbanwaterways.info/files/tajag.pdf
    • http://businessplan-capalpha.eu/mbp/upload/images/images/upload/ckfinder/natifivubanok.pdf
    • https://dcmheavyequipment.com/admin/images/file/88937309715.pdf
    • http://steffis-strassladen.de/userfiles/file/suzogi.pdf
    • http://musclecar-taps.com/js/upload/files/jikojisoza.pdf
    • http://trufeel.com/ckeditor/ckfinder/uploadfile/files/fususuzil.pdf
    • http://e-menu.hu/editor_up/ligipavaxogigujesaz.pdf
    • http://nguyenthaotech.com/upload/files/tuzivo.pdf
    • https://trsoftyazilim.com/genelresimler/file/30394939355.pdf
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130a86f21206---94382751455.pdf
    • http://bfcy88.com/uploads/files/zakup.pdf
    • http://0225674989.kad.tw/kads/ckfinder/userfiles/files/dekawufawepet.pdf
    • http://theseadiaries.com/ckfinder/userfiles/files/17682905754.pdf
    • http://nprofit.hk/userfiles/suveletefiditesiw.pdf
    • http://jutaek.humenia.com/upload/userfiles/2021/09/files/210906170140.pdf
    • http://jenistudio.com/upload/FCK/file/40711546584.pdf
    • http://landonintergroup.com/ckfinder/userfiles/files/bijabawasasamajikaz.pdf
    • https://gauravkankariya.com/wp-content/plugins/super-forms/uploads/php/files/8100667d46bb1c4947afe1ffdd63a071/kabozubowonofipujodovu.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=tb+guidelines+2018+pdf+zambia
    • 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_off0000e5b9.bin
2677b269d00d7fc9f0880e47ed69dd1d250cd2105608ec0185bc57c445b4bc2d
pdf-font-stream PDF embedded font (sfnt) at offset 0xE5B9 17720 bytes
font_01_sfnt_off00011442.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11442 16792 bytes
font_02_sfnt_off00012c59.bin
cddccd2bae26a657ffe6ce7eea6c859809564129a0dde4afe5351e4371aa94b3
pdf-font-stream PDF embedded font (sfnt) at offset 0x12C59 11288 bytes