Malicious PDF — malware analysis report

Static analysis result for SHA-256 de4bcb3cf369fc8e…

MALICIOUS

PDF

83.1 KB Created: 2021-03-19 21:40:10 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 978fb1f5dc38061ad3356e2752cc11f3 SHA-1: d4210b216bbbbb0ff0edbda2c51e77f46b1bd62b SHA-256: de4bcb3cf369fc8ec5dbd1cc9e88ca0c731dd90999e0a70365d4ac71945900e9
194 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, indicating a link farm designed to distribute traffic to potentially malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. The document body, though heavily obfuscated, contains keywords related to worksheets and answers, supporting the lure.

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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://pelibifir.ru/wix?keyword=impact+of+the+louisiana+purchase+worksheet+answers PDF link annotation
    • http://dilijox.22web.org/tubawumugomurotamovete.pdfIn PDF document text
    • http://jiludedo.iblogger.org/free_templates_html_email.pdfIn PDF document text
    • http://nexofozupugasi.mywebcommunity.org/bollinger_bands_squeeze.pdfIn PDF document text
    • https://wemivera.weebly.com/uploads/1/3/4/3/134311686/mivipekomanusuwoxa.pdfIn PDF document text
    • https://xabonawof.weebly.com/uploads/1/3/5/9/135965837/wuwabexibuviri_zajuri.pdfIn PDF document text
    • https://ginuwawabesinu.weebly.com/uploads/1/3/1/1/131164414/134045.pdfIn PDF document text
    • http://tozufokoxogo.22web.org/be_better_informed.pdfIn PDF document text
    • http://zunololanuxigu.sportsontheweb.net/how_to_factory_reset_jbl_flip_2.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://8d275f60-8e36-4e70-8574-b6d542a617c4.filesusr.com/ugd/dbf6c2_4bd96a074b9444c3a08cdc7fdeff92c9.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/e45c0546-117b-4751-961b-b07ecf4b8a50/juwusotulovedezajuguf.pdfIn PDF document text
    • http://fefiraxubuviwep.epizy.com/beduxe.pdfIn PDF document text
    • https://77bc4ea4-de20-41c0-a463-a5315db628d9.filesusr.com/ugd/2c69e3_cbb5d9fff5da412484cbaad8c7c58d3d.pdf?index=trueIn PDF document text
    • http://roveramo.atwebpages.com/gipusozivuf.pdfIn PDF document text
    • https://87b84290-c0b3-4c73-97a1-3d59c64c3f69.filesusr.com/ugd/c638b7_aa3c1a8729094ea088ef5fa606e6feb4.pdf?index=trueIn PDF document text
    • https://c183b790-cb34-49aa-848e-1a9f2b14dda3.filesusr.com/ugd/d8966e_3278ac1c901a4acaa6db81dff27c8b64.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/f92c74d4-9391-490e-89b8-2d2497adfc09/58551774150.pdfIn PDF document text
    • https://e24ff460-1725-4b9d-a7de-f8438c38fea0.filesusr.com/ugd/366850_aa234d05699e48e794d3ae96de232bdb.pdf?index=trueIn PDF document text
    • http://vabaxojivi.epizy.com/continuidad_de_los_parques_julio_cortazar_english_translation.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f86b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF86B 5232 bytes
SHA-256: bf648d5cffbb167e99f74e185fe0f8c3a3a5f50a5e584139590dcf7867a4f080
font_01_sfnt_off00010a12.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A12 11504 bytes
SHA-256: ac23ba7094fb1919c9face833ee53a353d8167b7624c5fb2e21c3e0c21d10340
font_02_sfnt_off000130a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130A5 4324 bytes
SHA-256: 1062cd8ddf90f4344fa193b395386d5669df1a952e5759311ca261a71931f361