Malicious PDF — malware analysis report

Static analysis result for SHA-256 9f538bc35cd7d6ad…

MALICIOUS

PDF

84.2 KB Created: 2021-03-12 06:09:24 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: c87d58819b5f056899462281ec81270f SHA-1: dfaf1fc8ba90af3dd622e17197b8d6d16bf17a0a SHA-256: 9f538bc35cd7d6ad3400c04fe9d19520fb67dcec01c23092156bb4ac136d78fc
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many pointing to disposable hosting services, indicating a link farm or phishing attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and numerous external URIs are indicative of a malicious document designed to redirect users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://leonvi.ru/123?utm_term=discord+formatting+superscript PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4494657/normal_600cf65a4aa3a.pdfIn PDF document text
    • https://cdn.sqhk.co/fapolokid/gdjhkgj/hack_robot_fighting_2_minibots_3d.pdfIn PDF document text
    • https://cdn.sqhk.co/masunidupag/gejibL9/49923106779.pdfIn PDF document text
    • https://xulakuvoloja.weebly.com/uploads/1/3/0/8/130813987/aa0baf.pdfIn PDF document text
    • https://cdn.sqhk.co/jotapepikota/ib6jdFx/fizefawune.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4445325/normal_5ff80c962eda7.pdfIn PDF document text
    • http://gexomafe.mypressonline.com/what_is_narrative_essay_slideshare.pdfIn PDF document text
    • https://cdn.sqhk.co/xavejapati/iegfYpV/wefipabejekekefufatozar.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4473916/normal_5ff7a83bcbbfd.pdfIn PDF document text
    • http://femuxeririta.mygamesonline.org/jijuvijazuketix.pdfIn PDF document text
    • https://cdn.sqhk.co/nogawevorus/xCS6icT/zombie_blast_crew_review.pdfIn PDF document text
    • https://netiwolofud.weebly.com/uploads/1/3/1/4/131438008/rodeganidasi-puwidumedi-sowabakubewuv.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4451217/normal_601dcaecbe8d6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4404490/normal_6016d589b43e6.pdfIn PDF document text
    • https://cdn.sqhk.co/fepexeguma/qgjgehj/garmin_basecamp_4._6._2_windows_10.pdfIn PDF document text
    • https://cdn.sqhk.co/givifevulo/LLieghz/rolling_stones_tongue_sweatshirt.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.opentle.orgIn PDF document text
    • https://f7cac2f2-528f-490f-9bef-cb2448a877de.filesusr.com/ugd/529ba0_6113ce56dfc84c15a1a682a31480f101.pdf?index=trueIn PDF document text
    • http://zotubune.myartsonline.com/21730658739.pdfIn PDF document text
    • https://907864b8-ab38-4b43-b195-7646ee37c451.filesusr.com/ugd/c4b402_75d8d9958eb446f281e992ecf3ebaeb5.pdf?index=trueIn PDF document text
    • http://lodumojokexiku.onlinewebshop.net/4307913274.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
    • http://www.gnu.org/licenses/gpl.htmlIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e372.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE372 5440 bytes
SHA-256: b08af94577ad92c4071c691b4684c9feb0f3e20a87834c0e677a27a4fbb9c2bd
font_01_sfnt_off0000f5d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5D9 7024 bytes
SHA-256: 59822f64519616c6b53c80896ccf607c15129699f7a2d746ab27a189519a1fe1
font_02_sfnt_off00010844.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10844 10796 bytes
SHA-256: 541912293f0e3b3a31b7239699c27650e5752a106d864388099f3b2d984806af
font_03_sfnt_off00012d82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D82 16140 bytes
SHA-256: a7bc05a3d52f5b82c2e9d68b1a8fa5de0b5a3fcaf3778fea092bb8d4d349a5a6