Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8dfdf54bfc7d8b2…

MALICIOUS

PDF

84.5 KB Created: 2021-03-22 11:20:40 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: fd2a530296bd66a6c7494bf36ca198a2 SHA-1: 290e24d38ec19a50928a50227fea7b348c211502 SHA-256: f8dfdf54bfc7d8b2bf477301cbc2aa1c3157d93823be09688eef6959d1ebafe4
184 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, with a critical heuristic firing indicating it links to known malicious redirector infrastructure. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body, though heavily obfuscated, contains references to 'wkhtmltopdf' and a date, suggesting it was generated programmatically to host these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://yafferge.ru/strik?utm_term=a+thousand+splendid+suns+character+chart In PDF document text
    • https://cdn.sqhk.co/sixajuzap/jhMeP6t/xegelewabowezeroliruzo.pdfIn PDF document text
    • https://cdn.sqhk.co/narulaloro/jaRifKb/world_of_bingo_free_download.pdfIn PDF document text
    • http://mowefopovog.mywebcommunity.org/why_is_my_samsung_refrigerator_not_freezing.pdfIn PDF document text
    • http://kurixuj.sportsontheweb.net/45095931181.pdfIn PDF document text
    • http://berkeciftci.net/catskill_daily_mail_obituary_archivespf39k.pdfIn PDF document text
    • http://creamwalls.online/what_can_you_do_with_a_public_relations_major0mm14.pdfIn PDF document text
    • http://sosiwawivijomo.scienceontheweb.net/94368792929.pdfIn PDF document text
    • http://jamotovoxut.mywebcommunity.org/breville_ice_cream_maker_recipes.pdfIn PDF document text
    • http://reduslim-ufficiale.website/figom5unpl.pdfIn PDF document text
    • https://cdn.sqhk.co/tajudozizif/ikcT5hj/foot_locker_promo_code_august_2020.pdfIn PDF document text
    • http://selectgetc.top/defending_jacob_season_2_episode_1o104m.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/xugigabitulu/navien_ncb_240_error_code_110.pdfIn PDF document text
    • http://mifojizu.myartsonline.com/30689634183.pdfIn PDF document text
    • https://35548484-ce42-4b18-9d9d-834326683263.filesusr.com/ugd/a221b6_01cac094769e4a8cb6c6d1d79e587942.pdf?index=trueIn PDF document text
    • https://c6926203-1eb9-401e-9afa-11f61f201807.filesusr.com/ugd/685707_60784526385840088a7d19c508cb30da.pdf?index=trueIn PDF document text
    • https://38aad9b5-7a72-45b8-ac81-9fe73ce82000.filesusr.com/ugd/08338c_6f4355830af44bacb3a9db576be2b94c.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/nonabafat/database_management_system_lecture_notes.pdfIn PDF document text
    • https://s3.amazonaws.com/kobivimelelo/26366429457.pdfIn PDF document text
    • https://3633ae4e-9acc-45df-885e-1bfa1481cb44.filesusr.com/ugd/e73054_2269200bb8fb4d4ab6726f0fbe5f76aa.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_off0000fabe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFABE 5152 bytes
SHA-256: f50985e52f0920ea54624adaf248a6e1fa45c6837f2fb7db67eede7f671d8565
font_01_sfnt_off00010c3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C3D 10180 bytes
SHA-256: 7d6e46a669cb628456c9a9320f0c0c547d3a5a9a70d55fe0bb2f64704f849e9c
font_02_sfnt_off00012f58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F58 16204 bytes
SHA-256: c988415812f594187b0a0ed75dc52802e798e1695b49bd300f8412a65040a449