Malicious PDF — malware analysis report

Static analysis result for SHA-256 b10bb6dbb2795ccf…

MALICIOUS

PDF

74.7 KB Created: 2021-06-05 02:24:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: e51ac655c0757f23ee54227750f85259 SHA-1: 2a5ca24f048cee602f31f7b44716cd6c36cd91ba SHA-256: b10bb6dbb2795ccfec3cc3ad6c0f126261babc9b85cb992678603f6882db932b
126 Risk Score

Malware Insights

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

The file is a PDF document identified as malicious by ML classifiers and ClamAV. It contains numerous embedded URLs, with one prominent URL pointing to 'krisoc.ru', suggesting a phishing or malware distribution attempt. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using multiple disposable hosts for redirection, further supporting a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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
  • 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://krisoc.ru/pbw?utm_term=simoniz+1900+psi+electric+pressure+washer+manual PDF link annotation
    • https://static.s123-cdn-static-d.com/uploads/4391921/normal_60b561c60db48.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4444852/normal_60b3d6b6a4e5d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4500665/normal_602d3cd1e0d4f.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4370087/normal_6001e2cc19cff.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4387701/normal_5fce8bb58f618.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4459341/normal_6033fbea0b5aa.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4405660/normal_60b80253bfa3b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4403262/normal_604ee7b7c7bd4.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4505159/normal_5fc5ea625547d.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/5730e15b-5702-424c-8c7d-410ffef39fab/ktm_380_serial_number.pdfIn PDF document text
    • http://pigedigasexu.pbworks.com/w/file/fetch/144505434/how_to_enter_service_mode_on_samsung_smart_tv.pdfIn PDF document text
    • http://nigezid.pbworks.com/f/86959922397.pdfIn PDF document text
    • http://pilujibos.pbworks.com/w/file/fetch/144500133/what_is_form_in_design_elements.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8e06215c-eb77-42df-80e1-15fefdd8ab0c/text_oh_danny_boy_deutsch.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/66c07300-c2fa-4a7f-9ce8-4ac1beef6a1e/mfj_949e_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3704b122-0566-44a4-ba00-d8b82f3693aa/is_the_ruger_sr22_pistol_a_good_gun.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c2c95b12-36cc-4b42-a485-05496e589641/kusokafevixuxi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/014ab76e-48b2-4ae7-9fbb-69ed77f834f8/rinnai_heater_propane.pdfIn PDF document text
    • http://mikabipi.pbworks.com/f/sitilevopivagawe.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/aa434f09-8f8d-48ed-bdfa-fbcd6ac3728d/kifewawibojesugakozege.pdfIn PDF document text
    • http://vaporezikumu.pbworks.com/f/mad_max_fury_road_full_movie_in_telugu_free_download_tamilrockers.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/24467993-0d4c-45b4-b59c-6fe3cff30f27/lodezixupuxaboxaratow.pdfIn PDF document text
    • http://bofamawetodo.pbworks.com/w/file/fetch/144634257/95097264540.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a2b9d2ff-4cbc-48aa-a533-bc1732ffe49d/how_to_build_a_gaming_pc_full_beginners_guide.pdfIn PDF document text
    • http://detomipipu.pbworks.com/f/bilingual_first_language_acquisition_annick_de_houwer.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_off0000e41c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE41C 5768 bytes
SHA-256: 7ebd0460e21687089f3e7fe143ae125c3e8862f09e645b082fc7c2bf2ea0f443
font_01_sfnt_off0000f7b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7B7 11052 bytes
SHA-256: 3c1048dd294b00ca3a5fc49d4860a70be2632d826fa231f33940d92f1e7ace86