Malicious PDF — malware analysis report

Static analysis result for SHA-256 2a873eaac6bcf713…

MALICIOUS

PDF

84.4 KB Created: 2021-03-20 19:49:53 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-02
MD5: fb18c53960ce25088e439162631df4ea SHA-1: 2e4ff61f7697908a971027be1028efa221d92a64 SHA-256: 2a873eaac6bcf7133b0a89f2062fb762873fa656152d1a500027c5e1272e8b61
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of external links pointing to various domains, many of which appear to be disposable or used for SEO manipulation. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or distributing further malware. The document body is heavily obfuscated and does not provide clear instructions, but the heuristic firings clearly point to a link farm strategy.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://lozipotod.ru/award?keyword=arpeggio+patterns+guitar+pdf PDF link annotation
    • https://gupovokezatiku.weebly.com/uploads/1/3/4/8/134878629/supifaxinetu.pdfIn PDF document text
    • http://lafutib.sportsontheweb.net/accounting_for_management_decisions.pdfIn PDF document text
    • https://xutagevobufoj.weebly.com/uploads/1/3/1/6/131607169/refivonidefukagabemo.pdfIn PDF document text
    • https://cdn.sqhk.co/kubepugemaki/zBjjMUS/download_game_larva_heroes_lavengers_2018_mod_apk.pdfIn PDF document text
    • https://xepovilebifupu.weebly.com/uploads/1/3/6/0/136086158/700611.pdfIn PDF document text
    • https://cdn.sqhk.co/koletexun/7gghgaB/vopidolaraziwumobosuzud.pdfIn PDF document text
    • https://lijepaxo.weebly.com/uploads/1/3/5/3/135324298/dfaadf3463b16e.pdfIn PDF document text
    • https://cdn.sqhk.co/gasariba/gdja2jj/maguliguzumanesatap.pdfIn PDF document text
    • http://kunepuvobimamin.medianewsonline.com/giwivinijobos.pdfIn PDF document text
    • https://mepodatadun.weebly.com/uploads/1/3/1/4/131452799/263030c597b6d.pdfIn PDF document text
    • https://vokuduvalabi.weebly.com/uploads/1/3/4/5/134502282/190d572e1fb16.pdfIn PDF document text
    • http://wigobike.sportsontheweb.net/pujodat.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://vujogosofeti.epizy.com/bmtc_application_form.pdfIn PDF document text
    • http://jutagejefutix.atwebpages.com/business_intelligence_analyst_resume_sample.pdfIn PDF document text
    • http://bowomufe.epizy.com/zezoruzutivepuriligerol.pdfIn PDF document text
    • http://parorusoba.rf.gd/14090234270.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bba8d147-2a4e-4db3-831e-f5f49e3bff94/zuboramaxubuzaselozegoxor.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8f59b351-999d-4152-810d-62984bb58fed/con_law_2_attack_outline.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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f6e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6E0 5164 bytes
SHA-256: 41e48026fa34242b48dc526923166a15deaa146e033a52f66cbe3e386017b835
font_01_sfnt_off00010882.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10882 11832 bytes
SHA-256: e54f1060b072c15c7a4c94a314b08bf9b4c993d820e08603f431db789ad1d680
font_02_sfnt_off00012f89.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F89 16120 bytes
SHA-256: 15a68420f1c377824b8c1fd571ac7c30556db1b4bc05006bf44ec3f6c6c83208