Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4859b45f044cfcf…

MALICIOUS

PDF

88.5 KB Created: 2021-09-09 04:15:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: ec27d62db2de19b61480234407c69a12 SHA-1: 0e5999e828742e93ccec965fed3ad238eb2edbc1 SHA-256: b4859b45f044cfcf5dc04a2db3e321025ef20a8c1b0e6d527a6d4558014af5dc
126 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. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic suggests it's part of a link farm on disposable hosting, pointing towards phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document, likely intended to redirect users to a harmful site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://impex-italia.it/userfiles/files/63577193578.pdf In PDF document text
    • https://argekaucuk.com/nbg/upload/files/10090670747.pdfIn PDF document text
    • http://rotarybrescello.it/userfiles/files/faragurume.pdfIn PDF document text
    • https://manajrgvaaradhi.com/cms-uploads/files/nulewe.pdfIn PDF document text
    • http://ybshajiang.com/userfiles/file/2021-09-03/210903135600557736do3pgnczwkjx.pdfIn PDF document text
    • https://www.creativetalentnetwork.com/ckfinder/userfiles/files/kedusenurulirodabapubufa.pdfIn PDF document text
    • http://szyuangang.com/UserFiles/file///difolizutil.pdfIn PDF document text
    • http://kasand.com/userfiles/61234597180.pdfIn PDF document text
    • http://workcoop.org/fckeditor/userimages/file/20210902180929.pdfIn PDF document text
    • http://jmestateplanning.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/39324669412.pdfIn PDF document text
    • http://vikohasanfiber.com/upload/files/gapopaxegemugexijali.pdfIn PDF document text
    • https://nullemont.fr/nullemont/ckfinder/userfiles/files/benakefiwepadajivoraboves.pdfIn PDF document text
    • https://samavetpharm.com/userfiles/files/76452264726.pdfIn PDF document text
    • http://tcgardening.com/userfiles/file/2021090506540173499.pdfIn PDF document text
    • https://padservhosting.com/userfiles/file/bajulenuxevewi.pdfIn PDF document text
    • https://guruamardaspublicschool.com/userfiles/files/sifuj.pdfIn PDF document text
    • https://zakarpattya-tour.com/upload/wokopanenakeje.pdfIn PDF document text
    • http://americandeliorder.com/uploads/files/25259208765.pdfIn PDF document text
    • http://monterroso-construpuntos.com/campannas/file/30703983531.pdfIn PDF document text
    • http://kovovyroba-nosniky.cz/UserFiles/File/38450897940.pdfIn PDF document text
    • https://cottingham-group.com/cufiles/files/vuxezirosepojusabisevijaw.pdfIn PDF document text
    • http://eunlocker.com/Images/Editor/file/2950758801.pdfIn PDF document text
    • http://ville-dammarie.com/ckfinder/userfiles/files/49912607760.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=10+interesting+facts+about+shakespearePDF 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_off0000f2c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2C1 18584 bytes
SHA-256: 9900cc7832fa8688686dd6854c1034c57eaabc144cb88c43a90187f12a1d0487
font_01_sfnt_off0001223f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1223F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013a56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A56 11124 bytes
SHA-256: decac32da6d835c6cc1937a28899ff0853b611bc1e321884c331d116e2423468