Malicious PDF — malware analysis report

Static analysis result for SHA-256 cdacedec5a40618e…

MALICIOUS

PDF

80.3 KB Created: 2021-04-11 21:26:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: f9fda41f386cdf9666cf52e672c8148a SHA-1: de57dc853fc6e27acad614910915605fa745a216 SHA-256: cdacedec5a40618ef41d6f41f9bbcd1ce96753624f37dfd7a59f8f7705851613
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, suggesting a link farm designed to redirect users to malicious sites. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and embedded URLs point towards a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://nipisod.ru/strik?utm_term=the+magic+school+bus+chapter+books+set PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4481406/normal_5fe38f638dde2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4488570/normal_602304ef8d10b.pdfIn PDF document text
    • https://cdn.sqhk.co/kewesowovim/dIQUjc4/hack_game_ppkp.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454694/normal_6034ff716f152.pdfIn PDF document text
    • https://cdn.sqhk.co/wofunukasu/8higc67/12804766531.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4481667/normal_5fecc61e818bb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4443823/normal_602af3763994b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4445570/normal_6065e0d7cb79f.pdfIn PDF document text
    • http://jijomaj.getenjoyment.net/adding_and_subtracting_positive_and_negative_integers_worksheet.pdfIn PDF document text
    • https://cdn.sqhk.co/xelalizogim/hibQtHj/wuvuged.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4482399/normal_6022748398231.pdfIn PDF document text
    • https://cdn.sqhk.co/vikafaselida/hahajeo/41536829043.pdfIn PDF document text
    • https://cdn.sqhk.co/fidisutipamu/iehjJww/vw_tiguan_driving_profile_selection.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4490534/normal_60524acc35464.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4402488/normal_5fd781cde26e0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4472753/normal_60259e2f5f3ef.pdfIn PDF document text
    • http://warixedivukinat.mygamesonline.org/tififoxoji.pdfIn PDF document text
    • https://cdn.sqhk.co/fimoviwaz/hihfsgi/76684829254.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://acfc0e76-311d-46af-9c13-f46c112eb424.filesusr.com/ugd/f90bad_eff162bb1a274e999dc08fce69b39702.pdf?index=trueIn PDF document text
    • https://95a57b4d-a24c-4412-bd87-88f4f885d252.filesusr.com/ugd/011e4b_159a3537342f4abfab1865a16ba3af2d.pdf?index=trueIn PDF document text
    • https://528f6e5c-6927-42ef-b7a5-a8f9c349750c.filesusr.com/ugd/07b979_5753cf277b3c4640a08cd24b66f5590e.pdf?index=trueIn PDF document text
    • https://7fad2989-91b8-457c-89bc-9a0e7aeef19f.filesusr.com/ugd/b03ff3_1e12116a5a66417d9731eee286b9865a.pdf?index=trueIn PDF document text
    • https://14535e1a-360a-4d01-a655-fa33e115c80e.filesusr.com/ugd/b222ea_b473ebddac204ec6a27037c1f0e7c22e.pdf?index=trueIn 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_off0000fa5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA5A 5500 bytes
SHA-256: aa6157bde0441f0d2dc1e094b6dcd2301a43e4821b750a3824499e6a0982abf9
font_01_sfnt_off00010ce3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CE3 11324 bytes
SHA-256: 03a29c861e2a0e3cd4c0c2b23e8fa689d78159e3345a7a01e90104cb6623a09c