Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf607a8f1d9dc71f…

MALICIOUS

PDF

81.8 KB Created: 2021-05-01 13:09:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 837f97319131aaf5d11875e1a55584e8 SHA-1: 87d9b5afbf2b20b507451a654a185b391135f897 SHA-256: bf607a8f1d9dc71fd1416abf5a3a07e174226bf0a207970605b8d77015f9af1f
186 Risk Score

Malware Insights

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

The PDF document contains a large number of external links, many pointing to disposable domains, indicating a link farm or SEO spam operation. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and numerous external URIs are indicative of malicious redirection or content delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://midufefew.ru/strik?utm_term=common+questions+asked+in+bpo+interview PDF link annotation
    • http://kunujunekedi.mygamesonline.org/physics_books_for_class_11.pdfIn PDF document text
    • https://cdn.sqhk.co/fularulojoze/hdijnWp/46921614028.pdfIn PDF document text
    • https://jevavuxenexek.weebly.com/uploads/1/3/5/3/135351486/guvaseze-labogitasagif.pdfIn PDF document text
    • https://cdn.sqhk.co/lasotepana/C4mr7hd/real_racing_3_wiki_cars.pdfIn PDF document text
    • https://cdn.sqhk.co/rogolafu/9Jthd8T/bitdefender_total_security_2019_software.pdfIn PDF document text
    • http://korefubelexusiz.medianewsonline.com/mosonitenumolikafal.pdfIn PDF document text
    • https://tirawinuzupufe.weebly.com/uploads/1/3/4/4/134445233/6394808.pdfIn PDF document text
    • https://joxedobiwot.weebly.com/uploads/1/3/5/3/135350216/getajadajugogebas.pdfIn PDF document text
    • https://mututekabifu.weebly.com/uploads/1/3/4/4/134466573/8266e3588a199a.pdfIn PDF document text
    • http://medolufinumul.sportsontheweb.net/bams_syllabus_2020.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/745801cd-3d23-4f4d-96c6-3741107ed529/5589762753.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/19d5c43b-8f0a-4189-8fdd-24db1d174afd/am_not_strong_enough_quotes.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cb12f11c-62d7-4aed-a92b-8e0bd0d17a2d/barrons_new_sat_28th_edition_free_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/36130d78-d130-41fb-8a5f-0d1e394ffa88/87118436638.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ffebca48-30cd-4451-9afb-dbf443aec0b4/mukumog.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3e88a139-5e0c-48ff-84ed-4a71d3c7ecb4/el_pequeo_vampiro_en_peligro_libro.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/eb95e2bc-c758-4e62-b476-165ad2eb90d9/60666615448.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c85bdcbd-d762-46e6-aeaf-4d7e79d8dcc7/how_much_does_office_depot_charge_for_screen_repair.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dd80fd59-325b-4ec5-a3f9-ea8c3af9ecbf/fonegetaxewuwigat.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cdd4a08e-d0fa-45c9-9cc3-9654f82f70a9/brady_games_final_fantasy_7_strategy_guide.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a43640bd-6519-4176-ac9b-23961071f344/when_will_the_maze_runner_death_cure_be_on_netflix.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8a75f1df-4b0e-4516-ba85-6041c0b39b00/how_to_know_if_your_baby_has_developmental_delays.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a51b0e61-1d3c-4d61-9d94-66bfbe734baa/bajar_la_biblia_reina_valera_1960_en_espaol.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_off0001000a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1000A 5460 bytes
SHA-256: 73d9c25ff30a09c63b666c461f0a28fe2ad6f6e2f27be22e3ac4f35d663da309
font_01_sfnt_off0001128c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1128C 11480 bytes
SHA-256: 3d494ccef05fe10a48644fdc6695f7b0ce91c0f26eb308117d954c182188286a