Malicious PDF — malware analysis report

Static analysis result for SHA-256 b53b7f3c2aff9b86…

MALICIOUS

PDF

66.5 KB Created: 2021-04-07 14:30:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-13
MD5: dee4cae3e0421f23c00de257fc9c102d SHA-1: d72e6e9dd24c017919e43e522fc7b72f674a6797 SHA-256: b53b7f3c2aff9b86f24dfbce9db8f89386aedd8b09d4f2d5e1a1c32c391b31b3
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a significant number of external links, many pointing to disposable domains, indicating a link farm or phishing attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were extracted, the sheer volume of external URLs and the nature of the heuristics point towards an attempt to redirect users to malicious sites, potentially for credential harvesting or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://lozipotod.ru/123?utm_term=bytebuffer+flip+android PDF link annotation
    • http://rubewox.sportsontheweb.net/cover_letter_sample.pdfIn PDF document text
    • https://tigibivimibi.weebly.com/uploads/1/3/4/3/134344299/f9f0bfef6c93c2.pdfIn PDF document text
    • http://gedirobidepud.scienceontheweb.net/biology_textbook_9_10.pdfIn PDF document text
    • http://purejup.iblogger.org/maria_theresa_of_austria_reforms.pdfIn PDF document text
    • https://mutikotamibe.weebly.com/uploads/1/3/0/8/130874320/8189674.pdfIn PDF document text
    • http://banikomapi.22web.org/46564543425.pdfIn PDF document text
    • http://goxamid.mypressonline.com/medical_bacteriology_and_mycology.pdfIn PDF document text
    • http://felesatediz.medianewsonline.com/pdf_alleluia_mozart.pdfIn PDF document text
    • https://sijotifibiga.weebly.com/uploads/1/3/0/9/130969940/e101f35f3ad5.pdfIn PDF document text
    • https://lusovajilabijix.weebly.com/uploads/1/3/5/3/135351537/9335480.pdfIn PDF document text
    • http://pedagodogiko.getenjoyment.net/how_to_set_up_a_paraffin_heater.pdfIn PDF document text
    • https://guvolobojifo.weebly.com/uploads/1/3/4/7/134733869/846e30557.pdfIn PDF document text
    • https://sabijodamibig.weebly.com/uploads/1/3/0/7/130775907/wefog_forekajufotukap_gabopuba.pdfIn PDF document text
    • https://fugejifok.weebly.com/uploads/1/3/4/1/134132056/metugovevomef_vixifu_tevabaxabi_fivus.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://muzokusadozejog.epizy.com/amd_radeon_vega_8_driver.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/885f4c04-13ee-4eda-85ce-81d3b694e0af/35801975221.pdfIn PDF document text
    • http://dujofaxuro.rf.gd/status_asthmaticus_information.pdfIn PDF document text
    • http://xidaxol.epizy.com/bijeziwibegopuwisaf.pdfIn PDF document text
    • https://35e1cc1d-5f6c-4a41-9b1b-b9ae8dddc97a.filesusr.com/ugd/351eee_18e12752727f47baa36544b1ec1ef394.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/811d022b-7963-4000-b2ff-037d4e0de2da/how_hard_to_study_data_science.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/12a6c0d2-101c-422a-8144-2882835b9c01/13_reasons_why_cast_season_3_episode_5.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d3ccd797-f841-4334-95bb-2b2e490575bd/dutagisulotilik.pdfIn PDF document text
    • https://08202b68-adf4-4b7d-bb06-fcebe54c78b8.filesusr.com/ugd/76dd3d_7cacbaa9e6e34e7290bc46f2eb6d1765.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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c5b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5B3 5148 bytes
SHA-256: ad55a31dd00a739423b7bfd90370e2ac5795b82b9d53dd0951835c8b4a61f305
font_01_sfnt_off0000d74a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD74A 11000 bytes
SHA-256: 745230bfc231f4268facfd9e43155f052422db95a03b18040416afe597f2533c