Malicious PDF — malware analysis report

Static analysis result for SHA-256 93e8592f2e743661…

MALICIOUS

PDF

82.9 KB Created: 2021-06-04 13:36:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 04227d8cbeeaefe4c4a9c391b94e4444 SHA-1: e22d63dc0a89903742edb1238050ee57db6f81ac SHA-256: 93e8592f2e7436612055a4510b9da7219bad11fa66e1d9687df8bef84c146988
186 Risk Score

Malware Insights

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

This PDF document contains a large number of external links, many hosted on disposable domains, suggesting a link farm or phishing attempt. The ML classifier and ClamAV detection strongly indicate maliciousness. The document body, though heavily obfuscated, appears to be a lure related to 'chemistry computing formula mass worksheet answers', intended to trick users into clicking the embedded malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://philabc.ru/pbw?utm_term=chemistry+computing+formula+mass+worksheet+answers PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4368756/normal_6048173f9eb63.pdfIn PDF document text
    • https://werijumifisa.weebly.com/uploads/1/3/4/7/134729585/9180822.pdfIn PDF document text
    • https://sigukelerodon.weebly.com/uploads/1/3/4/4/134491686/gotenewevofalemula.pdfIn PDF document text
    • https://rejileju.weebly.com/uploads/1/3/4/3/134335231/lofuweniw.pdfIn PDF document text
    • https://jumejavirufefe.weebly.com/uploads/1/3/4/7/134765112/fb8a6cae1a46.pdfIn PDF document text
    • https://somejokal.weebly.com/uploads/1/3/4/4/134494219/8632481.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4372399/normal_601223e277bc1.pdfIn PDF document text
    • https://wamokanudetavud.weebly.com/uploads/1/3/4/5/134510572/firuju-bedemos-zepinikolowe-pomoxopediw.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4426957/normal_605f6439a8835.pdfIn PDF document text
    • https://jutifakakunule.weebly.com/uploads/1/3/5/9/135985430/6818353.pdfIn PDF document text
    • https://vafuxukosa.weebly.com/uploads/1/3/4/4/134440110/cb20003d83f3.pdfIn PDF document text
    • https://lodewaga.weebly.com/uploads/1/3/7/5/137518990/kekal.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4486036/normal_5fdeeb07b3e06.pdfIn PDF document text
    • https://wixetaduzem.weebly.com/uploads/1/3/4/4/134471786/togamebi_buluvuwiz_tifafotolun.pdfIn PDF document text
    • https://bovidekomuburo.weebly.com/uploads/1/3/5/3/135312485/kamonenik.pdfIn PDF document text
    • https://wadaletabuj.weebly.com/uploads/1/3/2/6/132695896/5191135.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/5225de3b-c15a-435a-b5fa-0048472b7a41/how_to_simplify_square_roots_calculator.pdfIn PDF document text
    • http://bovojigu.pbworks.com/f/genubiv.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a0621f54-a601-473b-8915-7223700b5852/how_do_i_connect_my_dvr_to_my_network.pdfIn PDF document text
    • http://fadoposapat.pbworks.com/f/comparison_of_adverbs_exercises_for_class_5.pdfIn PDF document text
    • http://juvupumanut.pbworks.com/w/file/fetch/144509928/51073527223.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fd6341a2-d2e4-413b-ac3c-0b6cfd8034d7/8358869519.pdfIn PDF document text
    • http://xugilip.pbworks.com/w/file/fetch/144528009/daily_employee_attendance_sheet_in_excel_free_download.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001051d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1051D 5592 bytes
SHA-256: 868f79c9229d701834c566bfc6a49ef632b5fd959a8208cc4c6a58aa82350ad0
font_01_sfnt_off00011815.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11815 10976 bytes
SHA-256: 6eb91fd1ade90494020c931a380f17dc49458d1263440b7f801c2027a08d4b43