Malicious PDF — malware analysis report

Static analysis result for SHA-256 cfe7f64eb44c55b0…

MALICIOUS

PDF

76.3 KB Created: 2021-05-21 16:24:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: f08d346f38dafca5e8b2e3cafc7755a2 SHA-1: de9da9cb1fdb1cd0c9fde1491e3ee2a167654908 SHA-256: cfe7f64eb44c55b0d583b73f12dff8ee5609eb95c8e8681c0abe1dd96f04715d
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 0.9996

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://midufefew.ru/strik?utm_term=current+medical+diagnosis+and+treatment+2020+59th+edition+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4380536/normal_606242ee53d33.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4391303/normal_5ff230d0cb62d.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4411498/normal_5fc60571954cd.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4487662/normal_60279073b57e7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476453/normal_603519b9435f4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4410986/normal_60469d0e79ba4.pdfIn PDF document text
    • https://denibemexe.weebly.com/uploads/1/3/4/5/134597338/zeravirit.pdfIn PDF document text
    • https://zatitudebijozi.weebly.com/uploads/1/3/4/4/134460539/387d3814858d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4500678/normal_601813cdc6b56.pdfIn PDF document text
    • https://wojanoxunoliwam.weebly.com/uploads/1/3/5/3/135394081/fd8eabe.pdfIn PDF document text
    • https://rogetaguw.weebly.com/uploads/1/3/1/4/131407632/lurazojeka.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/wixatax/bunker_hill_security_security_camera_67139_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/013f1666-bb17-46ee-8a49-a84aac6025ce/how_long_to_harvest_iceberg_lettuce.pdfIn PDF document text
    • https://s3.amazonaws.com/kavalukato/el_libro_de_urantia_precio.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b6e7cd9b-919b-459a-be8a-44f910ad3d47/xuteweviwuliwitebasedi.pdfIn PDF document text
    • https://s3.amazonaws.com/nalifij/92199924916.pdfIn PDF document text
    • https://s3.amazonaws.com/ragejufa/vutajopaxef.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7ea1e38a-d0e0-4150-af19-5a602d74b557/rikutenijunadawubeg.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/532579fe-a5e1-43f2-92ef-bbce612e56a5/jumivomevu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b0b5566e-86c8-4cef-871d-70fceaa11c0a/how_to_become_transgender_surgery.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8bce826d-9487-4d40-9ef9-f30dc98b1c6e/11671454833.pdfIn PDF document text
    • https://s3.amazonaws.com/rozebofukixus/what_does_the_word_definitive_answer_mean.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_off0000eaa2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAA2 6028 bytes
SHA-256: 5b894c8157386759f5c83b78122a2734ba5b59116ab672e351719b9355544d1e
font_01_sfnt_off0000fef2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEF2 10576 bytes
SHA-256: 31f3082ac6bf96d76d1172de1fd6ba6b0af91a224adffea0893018d3376a94ad