Malicious PDF — malware analysis report

Static analysis result for SHA-256 1796b4017c1fa6f3…

MALICIOUS

PDF

80.6 KB Created: 2021-05-20 05:58:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: 6f3674044238a6d6902be65c5229b7ac SHA-1: df3065bae713c4d3fb018f1f46a53a21483b7cbd SHA-256: 1796b4017c1fa6f3c12c7fbe8c0647a4b1f8bec397e0d2673fa7d3112f8584e0
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://jottigo.ru/strik?utm_term=acs+biochemistry+exam+prep PDF link annotation
    • https://fodigedij.weebly.com/uploads/1/3/2/7/132740281/8924751.pdfIn PDF document text
    • https://fukuzemuk.weebly.com/uploads/1/3/5/3/135306557/sitigulowi.pdfIn PDF document text
    • https://vujewixijul.weebly.com/uploads/1/3/1/4/131437312/sidum-wasuwutesu-nigurelifi-jaruzusi.pdfIn PDF document text
    • https://sutowuvo.weebly.com/uploads/1/3/4/6/134685384/6591b1f9d.pdfIn PDF document text
    • https://rinotawobuv.weebly.com/uploads/1/3/4/7/134768279/sefuzeniwasowo.pdfIn PDF document text
    • https://zekigoduse.weebly.com/uploads/1/3/4/3/134336209/5180264.pdfIn PDF document text
    • https://boxavukexuzar.weebly.com/uploads/1/3/0/7/130775797/1973814.pdfIn PDF document text
    • https://jemewifawoboxe.weebly.com/uploads/1/3/4/8/134872293/nitebafepumebumu.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/047d448c-2f85-43ce-a5e2-2fe3664c02fe/vujabukubazobubul.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6aa0cdd8-576e-4914-9064-7cc75fa5af37/jandy_lx_pool_heater_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/70f1d776-c5df-49e9-8ee9-7e5c8a54ae23/how_to_get_abs_home_fitness.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2bcc2a21-24d6-4dc0-a673-719899027f7b/81866768227.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/250ef5da-6023-48a9-9aa3-6e7dd3efb43f/how_old_are_the_characters_in_pokemon_indigo_league.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9dce3171-0c68-4dd1-8a7f-1823804156af/niveles_de_prevencion_de_leavell_y_clark_mapa_conceptual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/deb004f9-da3d-4ff6-8fdb-7a6a2df5726c/desupulutexovunananal.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cffb53c7-47c5-463c-9925-ad1906fcd792/q-see_8_channel_h.264_dvr_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cbcd4512-892d-464f-9149-3d80e2ad2a26/37981774812.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d4a657c4-44ce-4658-b655-b186a5cc77f5/eating_for_life_chili_recipe.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8a8e646e-ba94-4311-8835-1461fe3b1dc4/16153573926.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_off0000fcc8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCC8 5440 bytes
SHA-256: 9f07cd25032d9a98e278ccb109c935410d6f00970314f6af0ac78f2d45279faf
font_01_sfnt_off00010f2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F2C 10800 bytes
SHA-256: 33f61be6043b25128c25b21b04d48d1d75303479957b88986a5bd87bf0cdd527