Malicious PDF — malware analysis report

Static analysis result for SHA-256 593df6ad3f73c11d…

MALICIOUS

PDF

85.6 KB Created: 2021-09-09 17:22:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-25
MD5: 0e3b28f3f818becd8ba482c14c00c46f SHA-1: aa82931fb31ed3aabef0b526f5c52c85074a296a SHA-256: 593df6ad3f73c11d74feb79a3279194c15fe652bb82b3f6df46e8da514841a46
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://krisoc.ru/uplcv?utm_term=multiplayer+games+wifi+hotspot+offline PDF link annotation
    • http://skontrolsengineering.com/file_media/file_image/file/sisolijolemipodax.pdfIn PDF document text
    • https://blsautomation.com/ckfinder/userfiles/files/xukipukugudomuxuko.pdfIn PDF document text
    • http://dentherapia.hu/files/file/33721652154.pdfIn PDF document text
    • http://genarchi.com/data/temp/file/46392851896.pdfIn PDF document text
    • http://rosabaum.de/web/editor/files/kepibizasebedutowokejarom.pdfIn PDF document text
    • https://beldapromosyon.com/calisma2/files/uploads/lolopazonizopori.pdfIn PDF document text
    • http://onlinepravenconsultant.com/uploads/wysiwyg/files/83555914649.pdfIn PDF document text
    • http://fusen-es.info/yamituki-n/uploads/files/69262014168.pdfIn PDF document text
    • http://zbirozskepodzamci.cz/userfiles/1281000911.pdfIn PDF document text
    • http://villapellegrino.it/userfiles/files/sulifapekuxapofep.pdfIn PDF document text
    • http://raegcafe.com/uploads/files/zuxinamuxivopez.pdfIn PDF document text
    • https://journalofcritique.com/ckdosyalari/upload/files/rudusabediki.pdfIn PDF document text
    • http://eskuvotoszkanaban.hu/editor_up/bazuteku.pdfIn PDF document text
    • http://czechdidgeridoo.com/admin/upload/file/29780885055.pdfIn PDF document text
    • https://kingwaterpure.com/ckfinder/userfiles/files/24430767536.pdfIn PDF document text
    • http://agecarekorea.com/ckupload/files/puramejafobiseg.pdfIn PDF document text
    • https://meesens.be/KrMee/Tekstverwerker/83066854064.pdfIn PDF document text
    • http://ambulatorioveterinariovianello.eu/userfiles/files/femanutigupamufopux.pdfIn PDF document text
    • http://svb-volleyball.de/userfiles/file/woromixelovagimabulozek.pdfIn PDF document text
    • https://satesayap.com/contents/files/fovifotin.pdfIn PDF document text
    • https://cottingham-group.com/cufiles/files/13862785454.pdfIn PDF document text
    • https://brigitte-farner.ch/userfiles/files/pokafuwerisogusezatibub.pdfIn PDF document text
    • http://nagyberki.hu/sites/default/files/fck_uploads/file/pajepawezenefumokutaseg.pdfIn PDF document text
    • https://eniedu.com/data/file/20210902201524.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_off0000e9e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9E4 11100 bytes
SHA-256: 5941d62e1f78fa0d109cb5fcacf06abb3d764c6d45115e27de6437d2b82a1b6d
font_01_sfnt_off000103b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103B0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011bc2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BC2 17384 bytes
SHA-256: f13ae44d9cbc882539d330c670a054131dc463cfcd647514f92b7f9932c64aaf