Malicious PDF — malware analysis report

Static analysis result for SHA-256 e4fdd994dfa8af77…

MALICIOUS

PDF

144.3 KB Created: 2021-06-21 17:47:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-24
MD5: 2461bf574bc7854c052c31bd870894aa SHA-1: 124cc2cbbb49b380d84ce6f67c46f528321d6f6c SHA-256: e4fdd994dfa8af7797570e14ef1a4aca8be412bd63cb0e929424020a18ce949b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to distribute malware or phish users. The document body, though heavily obfuscated, appears to contain metadata related to search terms, reinforcing the idea of a lure document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://krisoc.ru/uplcv?utm_term=matlab+for+engineers+5th+edition+holly+moore+solutions PDF link annotation
    • http://humanitool.ru/userfiles/file/33053245771.pdfIn PDF document text
    • https://thetitangroup.ca/wp-content/plugins/super-forms/uploads/php/files/d1d99e1aa4ecf829282373e153e93baa/kuvaxepuxa.pdfIn PDF document text
    • https://www.zulilighting.com/wp-content/plugins/super-forms/uploads/php/files/a56387341124fbbcd90307dadb2dc909/1445783742.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/a9d2c07db78d83be3f8cc8b20280e213/70363360341.pdfIn PDF document text
    • http://guojingmall.com/userfiles/file/%5C/26436070520.pdfIn PDF document text
    • http://hpworld.hu/data/pic/Image/file/kemubofazuzejidotive.pdfIn PDF document text
    • http://cleanyachts.it/writable/public/userfiles/file/47289639097.pdfIn PDF document text
    • https://www.llgnjinc.com/wp-content/plugins/super-forms/uploads/php/files/64f5fcb6c60ac9b384ad8591feec8278/73753538145.pdfIn PDF document text
    • http://nesemlak.com/test/images/uploads/files/57639140945.pdfIn PDF document text
    • https://dtcprojects.com.au/wp-content/plugins/super-forms/uploads/php/files/rsu30kjs00cctqgbpnr1qjvcf2/42347585877.pdfIn PDF document text
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608d4805a5df4---nivejigujukedovokij.pdfIn PDF document text
    • http://hit-air.pro/ckfinder/userfiles/files/5864471350.pdfIn PDF document text
    • http://12shio5.com/contents//files/18229799440.pdfIn PDF document text
    • http://ngpsusa.com/wp-content/plugins/super-forms/uploads/php/files/jbo6dsp0i4dlff1lfbk3m75cd4/30643039018.pdfIn PDF document text
    • http://matrixuniverzum.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160944e721d7ca---825805387.pdfIn PDF document text
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/ejb9tcn7unhtpqn4vd9cof9vlh/80861740716.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn 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_off0001dce4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1DCE4 5692 bytes
SHA-256: be854af8f5a9850c0a433703904b850083f4a081dff381a7e70848df91ba75f4
font_01_sfnt_off0001f031.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1F031 12988 bytes
SHA-256: 7a699e3da9f71e0393f0aa684b233e3cb003e6f64b257945118e3b6dc024b7b1
font_02_sfnt_off00021bfb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x21BFB 16192 bytes
SHA-256: b168039b654f979c140925a464ef75142322e9f7cc9a166e601b7839e62a3bff