Malicious PDF — malware analysis report

Static analysis result for SHA-256 01931fefc1fbb743…

MALICIOUS

PDF

71.8 KB Created: 2021-09-11 03:02:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: e5fbee671fe2e334972f623eea169e4a SHA-1: 0d6e7a520b8baedf0e7eb67809c06cbc35040bc1 SHA-256: 01931fefc1fbb743b8692cbb9921898e6b318a436f19bbf2b8500768d1c6b2b2
124 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and exhibits characteristics of a link farm, with numerous embedded URLs pointing to PDF files on various domains. Several heuristics indicate the use of compromised CMS uploads and disposable hosting, suggesting an attempt to obscure the true destination or host malicious content. The PDF document body is heavily obfuscated, but the presence of external URI firings and the overall structure strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier suspicious score 0.4060

Heuristics 5

  • 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
  • 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://fsoa.cn/userfiles/file/majipojilefegikofem.pdf In PDF document text
    • http://caopump.com/admin/userfiles/file/razutozomurerimiribilifux.pdfIn PDF document text
    • http://stellar.ru/ckfinder/userfiles/files/23798914504.pdfIn PDF document text
    • http://www.insight-assessment.com/ckfinder/userfiles/files/juxitofozipuvavazose.pdfIn PDF document text
    • https://rajaketiga.com/contents/files/75670839121.pdfIn PDF document text
    • http://rovitek.com/userfiles/file/wazemubixuzigodawomeboj.pdfIn PDF document text
    • https://drakbera.com/ckeditor/ckfinder/userfiles/files/15057316688.pdfIn PDF document text
    • http://rideabikenews.com/user_img/files/21920767478.pdfIn PDF document text
    • https://bio-obst-und-gemuese.de/userfiles/file/88728863699.pdfIn PDF document text
    • https://vitanov.rs/files/fofefolokubisemena.pdfIn PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/d6cfed155b47d574296e850744869910/72859453681.pdfIn PDF document text
    • https://www.clubmanizales.com.co/wp-content/plugins/formcraft/file-upload/server/content/files/16132844f28bde---58139055362.pdfIn PDF document text
    • http://herium.net/FileData/ckfinder/files/20210908_78968BE5C3DE0852.pdfIn PDF document text
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/1rj1q68eb36al8j6c36m3601eh/romuvod.pdfIn PDF document text
    • https://millersexpress.com/userfiles/file/jebowigorugoxidedizaj.pdfIn PDF document text
    • https://nailseasupportgroup.com/wp-content/plugins/super-forms/uploads/php/files/66f2484437a7f40cf3bedf01ef80696f/zojisetojazur.pdfIn PDF document text
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/ltvddov6c6uk9crdbgj3h7jt72/7181493557.pdfIn PDF document text
    • https://locktactyuma.com/ckfinder/userfiles/files/52831100698.pdfIn PDF document text
    • http://chanhungcorp.com/images/uploads/files/zupubugolarademivasol.pdfIn PDF document text
    • http://bluestandard.pl/ckfinder/userfiles/files/97194038451.pdfIn PDF document text
    • http://ore-processing.ru/d/files/35242007752.pdfIn PDF document text
    • http://zzquansu.cn/d/files/mulidetatujomero.pdfIn PDF document text
    • https://tranduongauto.com/app/webroot/files/images/pages/files/45824417221.pdfIn PDF document text
    • https://dalnoboy.com/data/filestorage/upload/files/koralureser.pdfIn PDF document text
    • http://rulada.by/upload/editor/files/34710368932.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=bridge+to+terabithia+chapter+4+pdfPDF link annotation
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ea56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA56 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001026d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1026D 10852 bytes
SHA-256: c0532ce5527bfc2f4a089309105f238fc48cc2400f06a02f092809e3b4648aed