Malicious PDF — malware analysis report

Static analysis result for SHA-256 fa21110a9fbcf97f…

MALICIOUS

PDF

95.5 KB Created: 2021-09-16 14:38:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: f2bd2c165eaf1b6e26f8cd2a0ae9e338 SHA-1: 879d05e53d8d65c0bd767a3f1959afb7a271a8ca SHA-256: fa21110a9fbcf97facdb003bdb664b1d5e75dfed792f2a0e2715fd6a959fa0bf
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a link farm detection and a high ML score, indicating malicious intent. The presence of numerous embedded URLs, many pointing to potentially disposable domains, suggests a phishing or malware distribution campaign. While no scripts were explicitly extracted, the PDF structure and link farm behavior are consistent with techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://lucky-erotic-massage-bucharest.ro/ckfinder/userfiles/files/tibapuralituvigavinuzu.pdf In PDF document text
    • http://ministerium.pt/files/wisefulasapegegero.pdfIn PDF document text
    • https://residenciasanamaro.es/userfiles/files/58303972871.pdfIn PDF document text
    • https://hotelexpert.ro/uploads/files/zajidorena.pdfIn PDF document text
    • https://democv.associasuite.com/imagenes/contenidos/files/muwunutegufobel.pdfIn PDF document text
    • http://easy-sleep24.de/shop/images/editorfiles/file/rowomas.pdfIn PDF document text
    • http://snnet.kr/board_pds/fckeditor/2021/09/file/sorep.pdfIn PDF document text
    • http://gospel-pour-100-voix.com/fichiers/newsletter/file/19669660271.pdfIn PDF document text
    • https://dalton-english.com/userfiles/file/podinoxaf.pdfIn PDF document text
    • http://aven.su/userfiles/file/girusigaturimerifujeru.pdfIn PDF document text
    • http://gccde.com/downloads/blog/geust/files/2191640910.pdfIn PDF document text
    • http://sutinlawkrabi.com/ckfinder/userfiles/files/35773636451.pdfIn PDF document text
    • http://www.village-gaulois.org/gestion/ckfinder/userfiles/files/66081531196.pdfIn PDF document text
    • http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/770ac4c546b0a7f4ea9da189ef76d406/74690208853.pdfIn PDF document text
    • http://odnoklassniki-files.ru/images/uploads/files/xobux.pdfIn PDF document text
    • http://cissi.it/userfiles/files/66616525378.pdfIn PDF document text
    • http://lustigersteirer.at/userfiles/file/20685886780.pdfIn PDF document text
    • https://suksesunited.com/contents/files/5766656256.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161323f57c6b8c---67868592556.pdfIn PDF document text
    • http://irk-yoga.ru/upload/files/20735056189.pdfIn PDF document text
    • http://rockbond-aac.com/id-admin/fckImages/file/48814036378.pdfIn PDF document text
    • https://ltes2.tw-goods.com/UserFiles/files/70640529406.pdfIn PDF document text
    • http://gainliving.com/upload/editor/file/92598456846.pdfIn PDF document text
    • http://optometrystaprzemysl.pl/userfiles/file/woseravilavimilepesudobe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=start+service+after+reboot+androidPDF 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_off00011156.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11156 17588 bytes
SHA-256: e467ed04859f7d7a66c5de19b982b6f624322d5c561f8daf38fc34a69d489882
font_01_sfnt_off00013f68.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F68 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001577f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1577F 10704 bytes
SHA-256: 0c64f7ddc65304552db6c03c50a5861f61c99c2799a8bef376d8bd66c235bd10