Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1e9c14a3ce09ca8…

MALICIOUS

PDF

70.9 KB Created: 2021-10-01 05:49:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 3aedd67ed96348b3392b368a5ffc45c3 SHA-1: 198cd6e30b49997dc0ffbc5961fc3ecbdf1dfe6a SHA-256: b1e9c14a3ce09ca8c0e6177442739f9d73253b813a12aa27c80efc47ae76bfd5
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple heuristic firings indicating malicious intent, including random URL links and being part of a link farm on disposable hosting. The ML classifier and ClamAV detection strongly suggest maliciousness. The embedded URLs likely serve as a lure to download second-stage payloads, aligning with a phishing or malware distribution attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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=android+set+default+password+manager PDF link annotation
    • http://www.julietlandau.com/fckeditor/userfiles/file/86838017415.pdfIn PDF document text
    • https://www.mds-horizons.com/upload/files/45451636361.pdfIn PDF document text
    • https://phunhai.net/upload/files/66252103239.pdfIn PDF document text
    • http://cz-synergy.cz/data/file/67554905058.pdfIn PDF document text
    • http://ambulatorioveterinarioscapindandrea.it/userfiles/files/tuselubu.pdfIn PDF document text
    • http://shukokai-voves.fr/userfiles/file/62671557067.pdfIn PDF document text
    • https://finliz.lt/i/File/90000418032.pdfIn PDF document text
    • https://indiansecuritisation.com/ckfinder/userfiles/files/jisukepalupudijogijozo.pdfIn PDF document text
    • http://fine-trading-knotwork.de/uploads/media/jekowuk.pdfIn PDF document text
    • https://yakin-surewin.com/media/file/76941089871.pdfIn PDF document text
    • http://zaintik.org/files/galeria/files/97421200898.pdfIn PDF document text
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1614d76f029d06---85467678365.pdfIn PDF document text
    • http://xn--h1aaebajlcgx.xn--p1ai/sadm_files/45437851418.pdfIn PDF document text
    • http://bernardthevenet.fr/ckfinder/userfiles/files/ferojudobib.pdfIn PDF document text
    • https://eravukappalpalli.com/userfiles/file/puvutolez.pdfIn PDF document text
    • https://thenovgorodspaceship.andreirozen.com/images/files/negagomuris.pdfIn PDF document text
    • https://bazab.ru/ckfinder/userfiles/files/sugosirozasune.pdfIn PDF document text
    • https://vsetinrally.cz/userfiles/file/nupid.pdfIn PDF document text
    • http://fields-on-earth.com/images/blog/file/97654935882.pdfIn PDF document text
    • http://myappartement.de/web/editor/files/getasopipitedunitodikamas.pdfIn PDF document text
    • http://zaintik.org/files/galeria/files/95402151174.pdfIn PDF document text
    • http://mentaplywood.com/images_upload/files/fejujopalijibakepiwojeza.pdfIn PDF document text
    • http://archetipoingegneria.it/userfiles/files/69077885068.pdfIn PDF document text
    • https://reazfarah.com/ckfinder/userfiles/files/nagorivepubatow.pdfIn PDF document text
    • https://alixdemassy.fr/userfiles/file/wenosux.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_off0000b2f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2F4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cb06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB06 15724 bytes
SHA-256: dc1db971020e124fc6989bc25a0f4268e9ed17a174b8b806ba6d5544f55ee34c
font_02_sfnt_off0000f297.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF297 11008 bytes
SHA-256: d6efb070d50c2ac8431980054f2871531fab0b518be6ce1743bca36bd68be8e6