Malicious PDF — malware analysis report

Static analysis result for SHA-256 7aa98be27fa258c6…

MALICIOUS

PDF

76.9 KB Created: 2021-09-12 12:08:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 1c3bcdb4e3029a2d5565994199002ec0 SHA-1: 54a34b369b902fe4c696260e8038e93487cfd46a SHA-256: 7aa98be27fa258c625681734e710f19babb11375d59546bc87cb3c53dcfe6ed5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with multiple embedded URLs pointing to potentially compromised websites or disposable hosting. The presence of these links suggests an attempt to lure users to external malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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 http://cathugo-catamarans.de/res/wysiwyg/file/kinubejabos.pdf In PDF document text
    • http://brilspa.ro/userfiles/file///zizovaleburor.pdfIn PDF document text
    • http://nc-israel.ru/upload/files/21904368676.pdfIn PDF document text
    • http://sangiorgioautoservizi.com/userfiles/files/37900114314.pdfIn PDF document text
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/16130daabce761---51838976843.pdfIn PDF document text
    • https://audit-advisers.com/userfiles/file/razazosavipi.pdfIn PDF document text
    • http://bouwbedrijfansing.nl/userfiles/file/85957341602.pdfIn PDF document text
    • https://lashmakerpro.it/wp-content/plugins/super-forms/uploads/php/files/8p6733gvdkg7ofeun3n0kfukc5/wodoviz.pdfIn PDF document text
    • http://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d7b40b1263---52625878013.pdfIn PDF document text
    • https://ozora.schaffsen.com/contents/file/93919247179.pdfIn PDF document text
    • http://kiko168.com/UploadFile/file/20210905073816952.pdfIn PDF document text
    • http://emiem.pl/public/upload/ckfinder/userfiles/files/8124772692.pdfIn PDF document text
    • https://domilot.com/uploader/files/68634308300.pdfIn PDF document text
    • http://crosswaysrecruitment.com/userfiles/file/wekijezakuvazosurugon.pdfIn PDF document text
    • http://salman-group.com/userfiles/file/38589628214.pdfIn PDF document text
    • https://abcoegypt.com/userfiles/files/98394655525.pdfIn PDF document text
    • http://karmand24.ir/basefile/ehotel724ir/files/17076157541.pdfIn PDF document text
    • https://nicklason.se/ckfinder/userfiles/files/gubuwimerun.pdfIn PDF document text
    • http://jkbprivateiti.com/userfiles/file/pikajogurijugenonozafuj.pdfIn PDF document text
    • http://patanamachine.com/imgUpload/files/nugekinajevojobev.pdfIn PDF document text
    • http://blpest.com/UserFiles/file/zajalix.pdfIn PDF document text
    • https://ceral.pl/ceral/pliki/file/taxemuv.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=wechat+move+to+sd+cardPDF 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_off0000c91f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC91F 10452 bytes
SHA-256: 421272c9e0adc895017ac726764ca2e3ccd913caaaab15cb0a7550d9c74c7377
font_01_sfnt_off0000e0ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0ED 17616 bytes
SHA-256: 21176b4f5725f06eadde7ce07c977032433e373364efd463ee8163a57b9ae255
font_02_sfnt_off00010e5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E5C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1