Malicious PDF — malware analysis report

Static analysis result for SHA-256 28bd67ac231a59e8…

MALICIOUS

PDF

78.3 KB Created: 2021-04-05 16:30:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: 6b75522a6f4e7e545976c1b721aad5ec SHA-1: 7b45c264cb8a242e1e10a6b227daa7ad6c208d03 SHA-256: 28bd67ac231a59e835e27e5fcdff641dabe523bef69f0217148b25d445cc3a5a
126 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, with heuristics indicating it's a link farm on disposable hosting. The embedded URI points to a suspicious domain, suggesting an attempt to redirect users to a malicious site. While no scripts were explicitly extracted, the PDF structure and embedded URLs strongly suggest a phishing or malware distribution attempt, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://jumiwimov.ru/award?keyword=catalog+template+pdf+free PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4486534/normal_604cda8c49760.pdfIn PDF document text
    • https://cdn.sqhk.co/dujagazatad/iMKigjj/75262459621.pdfIn PDF document text
    • http://italiahot.space/23169890018m6l14.pdfIn PDF document text
    • http://zesamoa.online/piano_music_theory_cheat_sheetfzo51.pdfIn PDF document text
    • https://cdn.sqhk.co/zatovafer/lEMhhgi/17663998667.pdfIn PDF document text
    • http://my-credit.info/sodastream_fizzi_sparkling_water_maker_black_with_mini_cylinderui56k.pdfIn PDF document text
    • http://worldthailand.fun/pokemon_emerald_online_game_unblockedbvuzz.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4406809/normal_602625d6cb82b.pdfIn PDF document text
    • https://cdn.sqhk.co/bepoweruga/a4ggZgh/38575834609.pdfIn PDF document text
    • http://miiliioner.xyz/kavubutemedirofisewazvp73.pdfIn PDF document text
    • https://cdn.sqhk.co/pifajaloro/ghLgjjc/69565506181.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4482415/normal_600a496edb907.pdfIn PDF document text
    • https://cdn.sqhk.co/panafilaputu/c5jbgdM/french_mountaineering_terms.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4452865/normal_604d26b90f387.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/714f98bc-f893-4dcd-adfe-f0723747d6a3/polo_ralph_lauren_coupon_2020.pdfIn PDF document text
    • https://s3.amazonaws.com/jusuberu/cinnamon_girl_guitar_tab.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b1ccd47b-e35e-4c92-81c4-9d76217d149a/why_did_my_samsung_fridge_stop_cooling.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/494ab86c-2511-46b4-af19-ba76f817ecbd/minn_kota_autopilot_compass_board.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/eddfd288-eafd-49c0-b074-3ea2fcfd29b1/mechanical_engineering_reference_book.pdfIn PDF document text
    • https://s3.amazonaws.com/xidazeze/42591956209.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/202382b9-6ebd-4701-9e39-1266b7b7c1bb/dexigaku.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5fff5cba-7b86-4768-a731-aafbb85cc994/cliff_swallow_or_barn_swallow.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/869c2fb1-a38f-4c03-ae30-708ba7c47ebb/marx_capital_volume_3_summary.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/db96359b-f74d-4c8c-9d12-1e825d4c4b49/psychoeducational_group_topics_for_substance_abuse.pdfIn PDF document text
    • https://s3.amazonaws.com/voxulija/badmaash_company_320kbps_songs.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6ebe7ac2-16f9-466b-804d-bd987b08b94c/54758310863.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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f683.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF683 5088 bytes
SHA-256: 4a82e62906c9139204c49bbc9b6d07de3d5845ecc98ab8855bb9e1e3c61c025c
font_01_sfnt_off000107bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107BB 10588 bytes
SHA-256: fa74090e75d09a6a8ab99900a30b7019d81241260bfd7d765e12efe2a266b208