Malicious PDF — malware analysis report

Static analysis result for SHA-256 98b075cbf71cea12…

MALICIOUS

PDF

84.5 KB Created: 2021-04-06 17:18:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 3935a16757838b166de81341eeabff3d SHA-1: b56cd5fa49899cdf1ba61d7b606f48d99df3e19d SHA-256: 98b075cbf71cea127959bd7d958371228e7936853ccbf06fbcd980165b8284bc
184 Risk Score

Malware Insights

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

The PDF contains embedded links directing to known malicious redirector infrastructure, specifically 'dafemum.ru'. The document body, though partially corrupted, suggests a lure related to PDF merging. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than 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.
  • 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://dafemum.ru/award?keyword=fusionner+des+documents+pdf+ensemble In PDF document text
    • https://cdn-cms.f-static.net/uploads/4376379/normal_60257b69eb637.pdfIn PDF document text
    • http://sport-stavki.fun/146844994096mu40.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384819/normal_601f410ed0c66.pdfIn PDF document text
    • http://file-id.ru/sifolulasobi0skqt.pdfIn PDF document text
    • http://polfact.site/19822140954cpkik.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4488130/normal_5fd9701ea0980.pdfIn PDF document text
    • http://trynon.xyz/acer_nitro_5_gaming_laptop_featureskcel7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4427095/normal_6047de952bf59.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4382974/normal_60175eb72a639.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4450427/normal_5ffe6c198e6ee.pdfIn PDF document text
    • http://itfamily.info/nouns_activities_for_class_67692o.pdfIn PDF document text
    • http://islemleriniz.org/80700706759ogb74.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4484154/normal_60556b2c0b13f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4387031/normal_602bdd4c9a33d.pdfIn PDF document text
    • http://reduslimitaly-ufficiale.site/bekerenobilijutadogagikg3uvn.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4456140/normal_601aaf08dee18.pdfIn PDF document text
    • http://soinjaga.ru/9147497720391h4k.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/e28159e9-25b4-4efa-911d-eca4bf489356/what_is_average_speed_write_its_formula.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/21902bf6-2620-4131-b2a1-70aeed93dd86/how_many_sins_are_listed_in_the_bible.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/26b4b5d7-ad8a-4a61-88c3-d565cc6f7430/voice_live_playoffs_2020.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3add0509-fd9e-4eb7-bb52-26962d6060c3/look_whos_back_back_again_lyrics.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ee67e0a6-bef2-4dcd-aa16-204f8d809a88/maytag_bravos_xl_washer_stops_at_spin_cycle.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/74163805-c0ff-4945-ba14-c8d8d2a4f54f/what_happens_at_the_end_of_the_heir.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/758f03c3-20bd-4007-9866-45c5c48c38b7/linux_bash_argument_example.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/30f14bda-23ea-47f1-b118-07556322a88b/nuwofefogazesitura.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://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_off0000f45c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF45C 5184 bytes
SHA-256: d33144261a34aa9a8e6e83b538bde4c15fb882f5624bc4a89779b6d268b48808
font_01_sfnt_off000105ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105EA 12664 bytes
SHA-256: 99b5b5cf9140adfec061045b14e73bb5d74cda610bf59a35d8d6b2629cdad3b9
font_02_sfnt_off00012d9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D9D 16104 bytes
SHA-256: d2703eec0843ee934b0a8bba7850da2550094fb4af61d17619ccbf35009047d2