Malicious PDF — malware analysis report

Static analysis result for SHA-256 795ee7386d3e3b5d…

MALICIOUS

PDF

70.6 KB Created: 2021-05-19 14:36:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 970a76767a1ab79b8583fae34c8ae32b SHA-1: 248c0f7018574bfc8b2a84e7be440c71727ae6b4 SHA-256: 795ee7386d3e3b5d856e3d726e9974fa19d8f46616b8d3ecbe693fc3aaef2aff
156 Risk Score

Malware Insights

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

The PDF file contains numerous external links, a common tactic for SEO poisoning or phishing campaigns. The heuristic PDF_SEO_LINK_FARM indicates a large number of external links, with one pointing to zajinet.ru, which is flagged as suspicious. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 5

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://zajinet.ru/strik?utm_term=worksheet+for+class+10+maths+chapter+1
    • https://xejulanuvupif.weebly.com/uploads/1/3/2/7/132740270/8635271.pdf
    • https://gitapizi.weebly.com/uploads/1/3/2/6/132683136/sozabak.pdf
    • https://cdn-cms.f-static.net/uploads/4490266/normal_604fe8106da8b.pdf
    • https://cdn-cms.f-static.net/uploads/4389352/normal_60409d2e0c0d6.pdf
    • https://cdn-cms.f-static.net/uploads/4427085/normal_6047687917c9b.pdf
    • https://ropidofizo.weebly.com/uploads/1/3/0/7/130738616/wirulakovedes-jakorokudare-kegibo.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/2204ff38-0c59-4777-a3e8-d7d78f5a13f9/sketchup_make_unique_greyed_out.pdf
    • https://uploads.strikinglycdn.com/files/18dda05f-26c6-4c62-85f4-91407a4ce984/zasikuvovil.pdf
    • https://uploads.strikinglycdn.com/files/85436609-2dd9-4c17-8f07-5942c4847c16/31104598636.pdf
    • https://s3.amazonaws.com/posufij/lagu_beggin_you_madcon.pdf
    • https://uploads.strikinglycdn.com/files/96acf162-7984-43ac-8f3c-c5ae4b7e4ac0/64736111869.pdf
    • https://uploads.strikinglycdn.com/files/43a0f6cf-86b9-46df-b66e-f5331128ed79/what_foods_are_good_for_inflammation_of_the_joints.pdf
    • https://uploads.strikinglycdn.com/files/1a799c46-3365-436c-a56c-3823fa3c59b3/how_to_connect_two_vtech_phones.pdf
    • https://s3.amazonaws.com/fizaxo/pyelonephritis_antibiotic_treatment_guidelines.pdf
    • https://s3.amazonaws.com/mixanaz/how_to_refill_a_canon_cartridge.pdf
    • https://s3.amazonaws.com/mupukesunobaga/ribafakelepaw.pdf
    • https://uploads.strikinglycdn.com/files/fa51c6c2-1358-42f7-a393-8433d2fff3d3/troy_bilt_lawn_mower_belt_replacement_deck_drive_belt_a94.pdf
    • https://uploads.strikinglycdn.com/files/4806e177-64a3-4170-a6ee-aa38fe83c944/70998506185.pdf
    • https://uploads.strikinglycdn.com/files/8f574652-2402-4252-90e5-e00e2cf42909/maze_runner_part_4_release_date.pdf
    • https://uploads.strikinglycdn.com/files/d416b036-99e7-4b94-b0c9-f5a8c11e9ff8/what_do_you_call_a_person_who_is_sensitive.pdf
    • https://uploads.strikinglycdn.com/files/227b11c5-aad8-4f60-9739-35c22b30a52f/is_there_an_it_chapter_2_book.pdf
    • https://uploads.strikinglycdn.com/files/244bcddd-768f-49d1-977d-40d3b69e097c/47978497544.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d7ae.bin
725f0e7c11def180e65420412842599b7b8472a1307220bffd5dce23a0b30b10
pdf-font-stream PDF embedded font (sfnt) at offset 0xD7AE 5528 bytes
font_01_sfnt_off0000ea64.bin
552023854f5da63f0636ef4473e81b1ba6027ae7766bd567542147fa863bf54c
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA64 10256 bytes