Malicious PDF — malware analysis report

Static analysis result for SHA-256 86725eed55ba9915…

MALICIOUS

PDF

82.0 KB Created: 2021-04-04 17:04:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-27
MD5: 0b1d9b65604137590c9f5c1561e62a01 SHA-1: 14deba9670abdef845ab149efc5fdc91d837014e SHA-256: 86725eed55ba99154bf342c12536a8b36db703f130879878902dfac0b1194feb
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, identified by the PDF_SEO_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM heuristics. These links point to various PDF files hosted on potentially disposable domains, suggesting a link farm or SEO manipulation tactic. 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 contains metadata from wkhtmltopdf, indicating it was likely generated programmatically.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://kuzutuzo.ru/award?keyword=abraham+lincoln+speech+pdf PDF link annotation
    • http://lofitner.buzz/7734291091t31mz.pdfIn PDF document text
    • https://vixevugipun.weebly.com/uploads/1/3/5/3/135327752/3388380.pdfIn PDF document text
    • http://salet.store/what_type_of_oil_does_a_troy_bilt_pressure_washer_takens28x.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4379369/normal_600030af04410.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476924/normal_603fbda03ca09.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4373259/normal_600d5c74dbd84.pdfIn PDF document text
    • https://buveziketi.weebly.com/uploads/1/3/1/3/131398526/5816933.pdfIn PDF document text
    • https://riledamulobav.weebly.com/uploads/1/3/0/9/130969772/nisof-mezisebenigevel-ragodudamagosi.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4412181/normal_5ff0878e95cc4.pdfIn PDF document text
    • https://rodazikajoreme.weebly.com/uploads/1/3/0/8/130874285/50938.pdfIn PDF document text
    • http://changepass.online/ukulele_strumming_patterns_4_4d4fg6.pdfIn PDF document text
    • https://tagojakiwuki.weebly.com/uploads/1/3/4/4/134444274/72df4.pdfIn PDF document text
    • http://kungfumalibu.com/how_do_i_turn_off_the_red_standby_light_on_my_samsung_tvpizaf.pdfIn PDF document text
    • https://katalajoguv.weebly.com/uploads/1/3/2/7/132740778/f5ca010ba79c10c.pdfIn PDF document text
    • https://rixagaxovexi.weebly.com/uploads/1/3/4/0/134000332/jadin.pdfIn PDF document text
    • http://wildber.store/small_business_ideas_for_15_year_oldsvxupi.pdfIn PDF document text
    • https://mewasopaligesar.weebly.com/uploads/1/3/1/4/131454012/dewijixodoposid.pdfIn PDF document text
    • https://fimezerix.weebly.com/uploads/1/3/4/4/134478386/6ef391f9b3846.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://s3.amazonaws.com/lepefi/tugudunisumonojawamewez.pdfIn PDF document text
    • https://s3.amazonaws.com/xixonu/tijove.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/66c49aec-12f5-43c2-9897-eb7ee6b7199d/mackie_1642_vlz_pro_manual_espaol.pdfIn PDF document text
    • https://s3.amazonaws.com/xabalaru/muxujudowataje.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0e0f6d3b-04ff-450f-8213-335c62546b42/delunilowitoje.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_off0000f5c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5C7 5232 bytes
SHA-256: 2b1b51acb35ddc596753b06dd72a82df1d8dbeac7b0972dddaeb3ef8fde03fcd
font_01_sfnt_off00010746.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10746 10824 bytes
SHA-256: 83f7cd2b217a187f61fb14716e992eb1d61f21d697cdd9a0b6f805459bfae583
font_02_sfnt_off00012c27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C27 4324 bytes
SHA-256: cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34