Malicious PDF — malware analysis report

Static analysis result for SHA-256 5dca4244191aeefe…

MALICIOUS

PDF

76.4 KB Created: 2021-05-28 05:57:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: d084fbdd6e8ef115acf7928267733aea SHA-1: c4da6eb7420b657fbd99fe382e9a804e9ab32972 SHA-256: 5dca4244191aeefe382de101f3e43a8297d5e970fa0a754a1a36f2e17eec741d
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains a large number of external links, many of which point to disposable hosting services and are likely part of a link farm. The document body, though heavily corrupted, suggests a lure related to importing digital certificates. The presence of numerous external links and the ML classifier's high confidence score indicate a malicious intent to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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://jottigo.ru/strik?utm_term=como+importar+un+certificado+digital+en+google+chrome PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4450034/normal_5fdbe438ee7b3.pdfIn PDF document text
    • https://duxojavuse.weebly.com/uploads/1/3/1/4/131483254/lujigeduv.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4386333/normal_5ffe713b816ad.pdfIn PDF document text
    • https://sesupukaxupasi.weebly.com/uploads/1/3/1/0/131070911/xorinuwabosugabisez.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369507/normal_606dd5cd38af7.pdfIn PDF document text
    • https://rojomitalo.weebly.com/uploads/1/3/4/4/134485393/jojoludow-mepubusapi-wekuzagar.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4407788/normal_60671945ef80c.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4450516/normal_5fe077221c018.pdfIn PDF document text
    • https://sonunupenoxomo.weebly.com/uploads/1/3/3/9/133986361/vukibi-mitufoloketuve.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417658/normal_600a4aa8d10e2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368748/normal_606e43430bc49.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4454425/normal_5fe02f43236c8.pdfIn PDF document text
    • https://xedatuvigino.weebly.com/uploads/1/3/4/5/134580066/geladilaxiriki.pdfIn PDF document text
    • https://matubupediguja.weebly.com/uploads/1/3/4/1/134131452/xutixadozipazijufap.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/ec1a6615-07a6-49c3-954f-41dc24bff44f/joke_book_online.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0807bf23-4810-4557-818a-f1b41d4ff4b9/solving_systems_of_linear_equations_by_substitution_and_elimination_calculator.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7402de3b-3dd0-4544-b1fb-7484f7652606/how_to_get_a_child_into_foster_care.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7bdb0e99-3dae-43a4-a63a-e592a2d01f02/top_20_cases_of_2020.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3b2bdf41-76d6-4a2d-bea8-256c70acbfce/sharp_lc_90le657u.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e910d5e2-410c-4a17-b16a-b2836f71a7e2/27376243040.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_off0000ede9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDE9 5296 bytes
SHA-256: acce18267933d585f10c32d297fa3b73ea3af084939f329f8c458ea51ed533b5
font_01_sfnt_off0000ffbc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFBC 11120 bytes
SHA-256: 11e55f604039bafa1c49604bcbb62dfefc69fb28eee0f4df5d4e2399d676609e