Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f269577fac72db2…

MALICIOUS

PDF

70.0 KB Created: 2021-09-18 08:30:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: c2ee618cabeceb110c6e0f3543d3fc58 SHA-1: 3c481abce27b3487ac0805576948adbf4b176258 SHA-256: 4f269577fac72db21767feb4328611c12b5beb1962c1fce2c38dfc3d10d29f8d
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a machine learning classifier and ClamAV, indicating malicious intent. It contains numerous embedded URLs pointing to disposable domains, suggesting a link farm designed to redirect users to potentially malicious content or phishing sites. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a tactic to obscure the true destination of the links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 https://nomylo.ru/uplcv?utm_term=george+rr+martin+books+pdf PDF link annotation
    • https://euroroma-bg.org/files/file/56780265178.pdfIn PDF document text
    • http://food-cloud.com/home/food-cloud/www/site/site/data/files/xisusifuzufup.pdfIn PDF document text
    • https://egokituz.eus/files/galeria/files/vobalodivarapu.pdfIn PDF document text
    • http://ned.ru/uploads/files/novozuwoxodubove.pdfIn PDF document text
    • http://cachnhietcacham.vn/Images_upload/files/zolopovujajefixujijanab.pdfIn PDF document text
    • http://adgroup.co/userfiles/file/5895637130.pdfIn PDF document text
    • http://futimisdev.com/userfiles/file/vumukifuzoluluja.pdfIn PDF document text
    • http://jdjcnc.com/upfolder/e/files/20210918082432.pdfIn PDF document text
    • http://xaydunglenguyen.vn/upload/files/55d5e1.pdfIn PDF document text
    • http://sinching.com/uploadpic/files/202109110446188478.pdfIn PDF document text
    • http://didongsinhvien.com/upload/files/95703968704.pdfIn PDF document text
    • http://dfanchem.com/upload/files/98652677772.pdfIn PDF document text
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613d41b5286ac---vusorukasuse.pdfIn PDF document text
    • http://alternativefitness.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613488b019ed7---5219709024.pdfIn PDF document text
    • http://tomgiongvip.com/uploads/files/file/46236590128.pdfIn PDF document text
    • http://molenat-energies.fr/molenat.com/images/editor/file/98521244646.pdfIn PDF document text
    • http://pk.mo/userfiles/file/wowoxuxaxese.pdfIn PDF document text
    • https://giaiphapthietke.vn/media/file/files/vibepawara.pdfIn PDF document text
    • http://www.salpasafarit.fi/tiedostot/files/8978500992.pdfIn PDF document text
    • https://red-adlay.com/upload/files/momokerubo.pdfIn PDF document text
    • http://lnhaihui.com/userfiles/file/20210913055927_528161991.pdfIn PDF document text
    • http://allivecoat.com/userData/board/file/detawefeb.pdfIn PDF document text
    • https://kingyao.com/uploadfiles/files/20210902_160400_1820.pdfIn PDF document text
    • http://issaproject.com/app/views/panel/ckfinder/userfiles/files/xokefipul.pdfIn PDF document text
    • http://rybarict.cz/webpagebuilder/ckfinder/userfiles/files/69206948202.pdfIn 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://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_off0000b196.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB196 15416 bytes
SHA-256: 879b3bfb10ab071b05604acb732e4582c449a42dc42f29348401c814298a64c5
font_01_sfnt_off0000d926.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD926 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f13d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF13D 11068 bytes
SHA-256: 28f9cb08948106275c46a3f21456821a70fc6ef44e43efef0f80154a1d50361a