Malicious PDF — malware analysis report

Static analysis result for SHA-256 b87851242e99246e…

MALICIOUS

PDF

80.2 KB Created: 2021-09-12 09:25:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 765aacbbb638c11c25e5845a0dccb8ad SHA-1: 97d93c6453d45dc72532f4e1d85e67fe6ebb09b6 SHA-256: b87851242e99246eaa4b1f7642a2f1df83d336d260c9a75fea18b12fdb2ff873
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to disposable domains, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and numerous embedded URLs suggest it's designed to redirect users to malicious sites, likely for further exploitation or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://coretry.ru/uplcv?utm_term=pi+bonds+are+formed+by PDF link annotation
    • https://coolinterier.sk/upload/files/81245525287.pdfIn PDF document text
    • https://semineebrasov.ro/printuri-fi/files/rolikakalubinunikufejude.pdfIn PDF document text
    • http://sinhorelli.com/userfiles/file/7151046371.pdfIn PDF document text
    • https://highlander-inn.com/assets/userfiles/files/takamameziregufituga.pdfIn PDF document text
    • http://mrs724.ir/basefile/drtiketcom/files/silupudejabikugugugafesi.pdfIn PDF document text
    • http://eminenceinc.com/userfiles/file/63007731190.pdfIn PDF document text
    • http://baschin-heizung.com/meineBilderAlbertGrundschule/file/xotufobakenivuganitinutug.pdfIn PDF document text
    • https://ewdel.cz/ckfinder/userfiles/files/51503199231.pdfIn PDF document text
    • http://haki.vn/uploads/files/tifafigopugewu.pdfIn PDF document text
    • http://www.pro9apps.com/app/webroot/files/uploadimagesfile/56638561052.pdfIn PDF document text
    • http://saaretravel.ee/images/file/17569217885.pdfIn PDF document text
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613ac509591f2---vafukulutezopijoxavazope.pdfIn PDF document text
    • http://wernitznigg.at/files/38639232982.pdfIn PDF document text
    • http://ndt-ultratech.com/files/60155943906.pdfIn PDF document text
    • http://cathyknightwaite.com/ckfinder/userfiles/files/20883519746.pdfIn PDF document text
    • http://amicalelaique-guyancourt.fr/ckfinder/userfiles/files/73672911329.pdfIn PDF document text
    • http://seednseed.com/admin/fckfiles/file/93782137332.pdfIn PDF document text
    • http://geofer.eu/userfiles/files/11131227466.pdfIn PDF document text
    • https://inchiriereelicoptere.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16132703cb56dd---11751796352.pdfIn PDF document text
    • http://lumieretvie.com/userfiles/file/32764461384.pdfIn PDF document text
    • http://wawa757.com/uploads/files/79772982781.pdfIn PDF document text
    • http://hoteldazegliotorino.com/userfiles/files/jipapigonekadeso.pdfIn PDF document text
    • https://osikovo.eu/webroot/img/content/files/20384703079.pdfIn PDF document text
    • http://gyermekhaz.hu/Content/site_images/files/45998445192.pdfIn PDF document text
    • http://coinproject.com/userfiles/image/file/mowakinipumenumedutojepek.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_off0000d474.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD474 10624 bytes
SHA-256: e14240c7e6663ee49414d962d0dca301691186ebd8fa5d1186c9bcfba1752303
font_01_sfnt_off0000ecbe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECBE 17904 bytes
SHA-256: a53d80a2920078a524b5da8ae8384894947fd58076b8483258dd694fb792252c
font_02_sfnt_off00011b47.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B47 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1