Malicious PDF — malware analysis report

Static analysis result for SHA-256 c98fb68cc3f423c7…

MALICIOUS

PDF

93.6 KB Created: 2021-04-01 01:41:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: 3329fb1f93636823d74e4dcc309188aa SHA-1: 2014df0b98c5477951311bff45de4bb35bbe2858 SHA-256: c98fb68cc3f423c78c9708148838178b03e31d006111974059e7cacf22a6066b
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document contains a large number of external links, many of which point to disposable hosting services, indicating a link farm designed to distribute malicious content or conduct phishing. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution via these external links. No scripts were extracted, but the PDF structure itself is used to host and present these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://xezojetit.ru/123?utm_term=civilization+5+basic+strategy+guide PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4407793/normal_600ce521cb3d4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4382414/normal_5fe82b4c77bc2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4452206/normal_5fd340cb319c9.pdfIn PDF document text
    • https://cdn.sqhk.co/litanamamusi/BXziiy4/pofeve.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4378410/normal_5fe308a313383.pdfIn PDF document text
    • https://cdn.sqhk.co/mubogasaven/jhcmSia/63472782514.pdfIn PDF document text
    • https://cdn.sqhk.co/wuwovodegi/TEhgmmW/golden_boot_premier_league_2019_winner.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/b8d9d9d8-6c62-4c74-af96-0ec96591a8c8/how_to_write_one_million_five_hundred_thousand_dollars_in_numbers.pdfIn PDF document text
    • https://e590c0d9-b694-44fb-9862-47327b30d8b0.filesusr.com/ugd/89363e_ed06669d80db4d87befc17ab69629478.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/a71682a9-d2c7-4db3-a36d-ba76a0432b36/78875054021.pdfIn PDF document text
    • https://12dd324c-696b-4d67-8c19-991f3eacec2c.filesusr.com/ugd/eeb7bd_cd04fd5460cd49dd80453942f5bc9cf7.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/846231d8-c1a1-4651-a0df-1489160360db/how_do_you_sync_a_serta_adjustable_bed.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1d14b33f-c454-4bc8-8c73-2f3e85fd40d7/where_are_karst_landscapes_located_in_australia.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d8333773-6564-494e-a3a4-b950db4c3727/where_is_usps_customs_located.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/46be9f41-5e04-42de-90c3-63da9bc48c44/61702333243.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6a91a2c2-3aad-4c34-9df5-a04a64ec6e2c/where_can_i_learn_to_write_calligraphy.pdfIn PDF document text
    • https://91c7bc9f-df77-4dbd-ae51-8bcf521f3e61.filesusr.com/ugd/1df9ea_db8e87fbf64d46d69a5a5b875ae0cd24.pdf?index=trueIn PDF document text
    • https://6376acfe-5884-4251-b3d5-19a03c044549.filesusr.com/ugd/de3d83_76d3a85dee9e4d528a1f35463cfef0a8.pdf?index=trueIn 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://scripts.sil.org/OFLIn 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_off00011b20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B20 5488 bytes
SHA-256: 4710db8fffdbcec5430db7969196f46ab446a691604e3bc3aee10753bfcd347d
font_01_sfnt_off00012de7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DE7 10900 bytes
SHA-256: 4c53c3810c2f6300603def1ce8a4a87db8764caa061c35d9957b9092356b4e43
font_02_sfnt_off00015354.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15354 16204 bytes
SHA-256: 532315dfdc59b350d447ad91845dd8cc72a836e684f536ab9a4305dc5b53fb8e