Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff8f2be222360438…

MALICIOUS

PDF

75.0 KB Created: 2021-05-30 21:31:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: 1f66cd775164b99dd54bfb3e56777154 SHA-1: 947a85f00478944d4d379f5e066c337c8491e254 SHA-256: ff8f2be2223604383c5600a94c4b171e1d71ce105b826aa7fe60ebc32345fa0e
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, specifically as a phishing or SEO spam document. It contains a large number of external links, many pointing to disposable hosting, suggesting an attempt to drive traffic to various websites. The document body, though heavily obfuscated, contains metadata related to "assignment cover page design" and the wkhtmltopdf tool, indicating a potential lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://golowaki.ru/123?utm_term=assignment+cover+page+design++free PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4413347/normal_60072e8a966a8.pdfIn PDF document text
    • https://zutafagufagupak.weebly.com/uploads/1/3/4/2/134235067/savokifoz_nosogadoku_basuwudibifosu.pdfIn PDF document text
    • https://xolavubapipivuk.weebly.com/uploads/1/3/5/3/135302485/koroxeb-nutiwukujufup.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446168/normal_5fd8d5ea40815.pdfIn PDF document text
    • https://kutusavirub.weebly.com/uploads/1/3/4/2/134265758/5006359.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4414869/normal_60afe59f392f4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4403531/normal_604333dc34389.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4365560/normal_6001018acf716.pdfIn PDF document text
    • https://kuwesitupimanu.weebly.com/uploads/1/3/4/0/134095951/lusexir_manaxewirivax_kosula.pdfIn PDF document text
    • https://lorotorerusut.weebly.com/uploads/1/3/1/4/131452969/texosajawotorasu.pdfIn PDF document text
    • https://sumolepixa.weebly.com/uploads/1/3/4/6/134635742/957627.pdfIn PDF document text
    • https://rowopubogapog.weebly.com/uploads/1/3/4/2/134234702/9036543.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4483873/normal_60307914a589c.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4475216/normal_6008b624b7a3a.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/874006a3-9620-46c1-ac0c-a04bc26de941/flowchart_software_free_download_full_version_for_windows_10.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/edb8ba84-27e4-4e94-9a03-f343e1767765/body_for_life_eating_plan.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c5e35235-b86b-47a6-bd4f-f874c4ddfc96/formulas_para_obtener_el_volumen_de_los_cuerpos_geometricos.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7dabbe46-8d60-4ac3-8cb2-2e02b8007731/lexatepava.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8ce178a7-cbf5-4c75-858a-f1d0604defcf/gowutikobediriditot.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ea47b3e8-8b30-4c77-b842-fb793a7e63d9/gaggia_brera_user_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4633ce8e-3bae-401b-885c-96edc6096595/manual_de_organizacin_y_funciones_del_minsa_2019.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/26966d41-c363-4baa-afd2-f17657f27473/29660898171.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_off0000e88d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE88D 5492 bytes
SHA-256: d0abc9adeb3b473a2fb7389a01f097b226bd40cdf29e5829fd9c1841a3a774bc
font_01_sfnt_off0000fb37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB37 10324 bytes
SHA-256: cd0c1046f7d0d6cdac4a725e1531881396441e2a5f136e5f33c0e09884f34716