Malicious PDF — malware analysis report

Static analysis result for SHA-256 8cdd9a7f4e4f66d9…

MALICIOUS

PDF

84.4 KB Created: 2021-09-23 06:10:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 40ae65ff132dd3bc7648a47c3b1cc199 SHA-1: 5320907d2254c9a1b248c0f081649d20298f8067 SHA-256: 8cdd9a7f4e4f66d958e48b7c030c73ed8b7f6e4a332c54a37f584bd79fbd2a0f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous embedded URLs, many of which point to potentially untrusted domains, suggesting a link farm or redirection mechanism. The presence of PDF-specific heuristics like PDF_SEO_DISPOSABLE_LINK_FARM further supports the classification as a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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
  • 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://locoffice.ru/userfiles/file/kisinagulumexowomenaxaret.pdf In PDF document text
    • http://lesmashclub.com/imgUpload/files/tibukovif.pdfIn PDF document text
    • http://wksystems.net/HotelEstimator/userfiles/file/fovozawelamigul.pdfIn PDF document text
    • http://sluchatka-shop.cz/files/upload/files/gojatuvewinogizi.pdfIn PDF document text
    • https://cuichi177.com/uploads/files/202109130650374296.pdfIn PDF document text
    • https://costumeworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613100bdcfe0c---wabizomori.pdfIn PDF document text
    • https://alhurwallpaper.com/Files/files/bumoreguwoburupelik.pdfIn PDF document text
    • http://ckrestaurantgroup.com/ckfinder/userfiles/files/61687547494.pdfIn PDF document text
    • https://sunsoftinfoway.net/ckfinder/userfiles/files/72376054265.pdfIn PDF document text
    • https://presentkompaniet.com/img/content/file/saselilifupufubaf.pdfIn PDF document text
    • https://presstone.hu/userfiles/file/49547063464.pdfIn PDF document text
    • https://willmarareachamber.com/ckfinder/userfiles/files/devomuxuluwoxo.pdfIn PDF document text
    • http://praguynakorn.com/praguynakorn/picture/datapro/files/fumum.pdfIn PDF document text
    • http://tasarimak.com/ckfinder/userfiles/files/22529585723.pdfIn PDF document text
    • https://jasz-pap.hu/UserFiles/file/85539206582.pdfIn PDF document text
    • http://tokstar.com/_UploadFile/Images/file/14942958234.pdfIn PDF document text
    • https://buyafranchise.org/files/files/59194172779.pdfIn PDF document text
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/676d31a094be0efbda4f8d8ef3cde566/xuxotozoza.pdfIn PDF document text
    • http://midesignvn.com/uploads/files/medefaxasoduxir.pdfIn PDF document text
    • http://dongbanja.com/userData/ebizro_board/file/74768830715.pdfIn PDF document text
    • https://hantverksakuten.se/ckfinder/userfiles/files/zulelajumetilokag.pdfIn PDF document text
    • http://3wsystems.com/shipinc/userfiles/files/31274436619.pdfIn PDF document text
    • http://quocteanviet.com/img-chamthi/files/bobiwaxanijar.pdfIn PDF document text
    • http://digitalqwerty.com/ckfinder/userfiles/files/73203737333.pdfIn PDF document text
    • http://sperrincaravans.com/images/file/4942155654.pdfIn PDF document text
    • http://gartenmessebau.de/uploads/files/16552305876.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=revit+mullion+familyPDF 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_off0000e0c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0C1 10432 bytes
SHA-256: 64aff11ff3ccb59abe202c1895d88a0d0a61b13b6740814ffe852a9e11ce4c9e
font_01_sfnt_off0000f870.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF870 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011082.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11082 19640 bytes
SHA-256: 71fcd1cfcb4f135906fad60f7588276523f3fc6fc4ad80b5548dc36cff960530