Malicious PDF — malware analysis report

Static analysis result for SHA-256 808686e13c9d5835…

MALICIOUS

PDF

71.5 KB Created: 2021-05-07 18:44:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: c106e5d313fe7ca446d75629ed084e57 SHA-1: 79dd21fa95dfd6b090f382e99d618f65dc517c21 SHA-256: 808686e13c9d583571a370b57c3148f748b98829241f844adcaa050bbb6204c0
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, identified as a 'PDF link farm' heuristic. The primary malicious URL, https://jacksth.ru/strik?utm_term=algebra+word+problems+book+pdf, suggests a lure related to educational content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for SEO manipulation or to distribute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 5

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://jacksth.ru/strik?utm_term=algebra+word+problems+book+pdf
    • https://dokupikojezox.weebly.com/uploads/1/3/4/7/134740590/nudinexisax-dojorumefe-noxadekudu-bagewewow.pdf
    • https://cdn-cms.f-static.net/uploads/4407313/normal_6031bf62aff1b.pdf
    • https://cdn-cms.f-static.net/uploads/4443823/normal_6016015789e42.pdf
    • https://cdn-cms.f-static.net/uploads/4465142/normal_6050c541168c5.pdf
    • https://jopixumux.weebly.com/uploads/1/3/4/7/134734794/8419622.pdf
    • http://ita-talia.fun/9245556782jx6m4.pdf
    • https://cdn-cms.f-static.net/uploads/4419412/normal_603a941c4502c.pdf
    • http://kejamezegujoz.iblogger.org/wound_care_guidelines_2018.pdf
    • https://cdn-cms.f-static.net/uploads/4493245/normal_602b62ad35521.pdf
    • http://edarudost.online/95719154128v2dsu.pdf
    • https://xizovetezewo.weebly.com/uploads/1/3/2/8/132814166/6254463.pdf
    • http://tawabuzawi.iblogger.org/data_structures_and_algorithm_in_c.pdf
    • http://tadaziwazifumiw.iblogger.org/business_intelligence_python.pdf
    • http://tuwuradozanava.iblogger.org/curso_ilustracion_botanica.pdf
    • https://cdn-cms.f-static.net/uploads/4417807/normal_60250dc3b9c42.pdf
    • https://cdn-cms.f-static.net/uploads/4485705/normal_60318fa09cdb6.pdf
    • https://cdn-cms.f-static.net/uploads/4386081/normal_6068aa8919454.pdf
    • https://xuxasogunoniku.weebly.com/uploads/1/3/1/8/131856570/239a9d3.pdf
    • https://cdn-cms.f-static.net/uploads/4478146/normal_600f3ee7b9236.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://tomuvonunilo.epizy.com/vateguje.pdf
    • http://delifas.epizy.com/americanah_book_pages.pdf
    • http://zozoresupiz.epizy.com/vijomuxadikoka.pdf
    • http://pidulenumasan.epizy.com/zixago.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d8ae.bin
31ba85106a71d0267f51a5ec43fe371b6c8fd2a9740861f544bf3d9060dd0d2c		 pdf-font-stream PDF embedded font (sfnt) at offset 0xD8AE 5648 bytes
font_01_sfnt_off0000ebda.bin
e67e7581e1c6e76b1f23e51cd031fd2298e5dd6f3f18a72d6d746150b86449f6		 pdf-font-stream PDF embedded font (sfnt) at offset 0xEBDA 10756 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.