Malicious PDF — malware analysis report

Static analysis result for SHA-256 9217a397915fa129…

MALICIOUS

PDF

72.8 KB Created: 2021-06-11 02:16:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 5754bb8638bd4529170ef81edd2f77ff SHA-1: a8aa689d27cda078668d60afa595b29f1876b505 SHA-256: 9217a397915fa1299bc09d6c181d301946c2223d3b6ee358ed2dfabd0b5ca972
194 Risk Score

Malware Insights

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

This PDF document is identified as malicious by ML classifiers and ClamAV, exhibiting characteristics of a link farm designed to redirect users to potentially harmful sites. The heuristic findings indicate a large number of external links, many hosted on disposable domains, suggesting a phishing or malware distribution scheme. The embedded URLs, such as the one pointing to 'krisoc.ru', are likely part of this malicious infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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=decrease+pdf+size+to+200kb PDF link annotation
    • https://pozitolize.weebly.com/uploads/1/3/4/3/134330731/naruboma.pdfIn PDF document text
    • https://sirawomaperuli.weebly.com/uploads/1/3/1/3/131398091/3060278.pdfIn PDF document text
    • https://koxowuberes.weebly.com/uploads/1/3/1/3/131379375/0a65c3b3b356.pdfIn PDF document text
    • https://leludexubivavij.weebly.com/uploads/1/3/1/8/131860378/7520933.pdfIn PDF document text
    • https://kemizanina.weebly.com/uploads/1/3/0/7/130738765/xiwezelokozanepak.pdfIn PDF document text
    • https://lusugola.weebly.com/uploads/1/3/4/5/134599647/tibareligaderigak.pdfIn PDF document text
    • https://malekijewa.weebly.com/uploads/1/3/0/8/130813883/4896862.pdfIn PDF document text
    • https://gudesikoz.weebly.com/uploads/1/3/4/3/134374550/1c9f15a4.pdfIn PDF document text
    • https://lokejarezuwomi.weebly.com/uploads/1/3/0/7/130776656/4047802.pdfIn PDF document text
    • https://tudiputowol.weebly.com/uploads/1/3/1/4/131452732/wugebugep_jelagu_laguv_gemimevud.pdfIn PDF document text
    • https://kovibokasekur.weebly.com/uploads/1/3/4/8/134880184/2906671.pdfIn PDF document text
    • https://nigepopevoxi.weebly.com/uploads/1/3/4/8/134881291/pedimuvezosip-kilezoj.pdfIn PDF document text
    • https://fevenegor.weebly.com/uploads/1/3/1/3/131380973/kovolalagar-mukajonaxisu-sisujuvolikazi.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/03b6b9c4-0746-4dfb-92f1-5a1d6b58e1c0/robert_graves_greek_myths_audiobook.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/49a7ce02-f40b-47e4-a134-913df2cd273d/preventive_maintenance_checklist_format.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ae9ab989-c270-4e56-8f03-91e090bcfa90/the_sandman_tv_series_release_date.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7e1c9dbc-0afa-4ebf-b905-1f5efeed6c85/nursing_diagnosis_examples_for_pain.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b4781cc3-f20b-45ab-99c8-9215daef73ac/1578941997.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bb43a000-d662-4c1c-98c8-98c7c20f2ec2/gisimukisuw.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0b2d94bd-4823-4d40-873c-ee8b7a63565d/what_is_the_strongest_intermolecular_force_present_in_h2o.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_off0000dd55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD55 5644 bytes
SHA-256: edbcaf3edf8babc103d622efd806e73caf18222b4d62bb9b2fe70f9e2ae874af
font_01_sfnt_off0000f0a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0A3 10960 bytes
SHA-256: 6e51fc694c399c22d9a773a7ef0b149c69116f98c8c674d99b1b15f10bd67d93