Malicious PDF — malware analysis report

Static analysis result for SHA-256 9441e6ab637f92db…

MALICIOUS

PDF

82.0 KB Created: 2021-05-10 11:24:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 6f85672ad7b48a714f0f3fb75f29f795 SHA-1: eff72177b7e8528862769564ae996474ed90ff5e SHA-256: 9441e6ab637f92db4957f074683861fb0fb4a3bad095785241491b1af4ccddd4
194 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 hosted on disposable domains, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were directly extracted, the PDF structure and numerous URLs point to a phishing or downloader attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://kuzutuzo.ru/strik?utm_term=realidades+2+workbook+1b-6 PDF link annotation
    • https://fopunideneluw.weebly.com/uploads/1/3/5/9/135965314/2531006.pdfIn PDF document text
    • https://cdn.sqhk.co/puzusagilem/fnhb7gf/laporan_pendahuluan_bblsr.pdfIn PDF document text
    • https://cdn.sqhk.co/vazoguzo/ESgfosb/99418993876.pdfIn PDF document text
    • https://cdn.sqhk.co/nexetifosam/YhaQDjh/18_cartoon_tv_series_download.pdfIn PDF document text
    • http://nisisigewu.iblogger.org/ashrae_handbook_fundamentals_free.pdfIn PDF document text
    • https://cdn.sqhk.co/dodazija/FIsibaW/f150_fold_up_bed_cover.pdfIn PDF document text
    • https://cdn.sqhk.co/jujifefa/ckjahjy/jexajo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4382974/normal_602b0894b3ebd.pdfIn PDF document text
    • https://cdn.sqhk.co/waximanodif/Uidhdgi/electron_configuration_of_sulfur_in_sf2.pdfIn PDF document text
    • https://cdn.sqhk.co/jubawiwa/hHN5eFI/girl_ludo_king_game_app.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4417664/normal_5fe29c04029b0.pdfIn PDF document text
    • https://jadusulad.weebly.com/uploads/1/3/4/7/134764450/luwezisuzomigomekojo.pdfIn PDF document text
    • https://cdn.sqhk.co/bidomutarili/hbfoNKj/nojumo.pdfIn PDF document text
    • https://cdn.sqhk.co/butexuvokufo/gJhhha9/jimu_robot_app_for_windows.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://7a48fde5-f9d1-4ce4-84a2-8b156d245d18.filesusr.com/ugd/8127dd_0c53ddbf654b4a56b7628e9797471928.pdf?index=trueIn PDF document text
    • https://4fbc56e1-d9a2-4996-be1d-38f9cd263936.filesusr.com/ugd/b1afee_cac5d5f5ffea476ba63d6f713050f5e1.pdf?index=trueIn PDF document text
    • https://aa6d2f86-95e2-42cc-897e-6bbd71c3a116.filesusr.com/ugd/78daac_d8c2f56ab3a74c5f99d5ccdc993962ab.pdf?index=trueIn PDF document text
    • http://mutifesojare.epizy.com/69308012765.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_off00010051.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10051 5492 bytes
SHA-256: 13f392438feb896111df1bde55826a3ca8cec5742b08bc5d59b66e5dc676a41b
font_01_sfnt_off00011333.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11333 12032 bytes
SHA-256: 0580dc1d9c5a5e0247b27a2510f2ea875d1268130d9ffb265ef8d7494a0037ed