Malicious PDF — malware analysis report

Static analysis result for SHA-256 4dc98b87da1d85c0…

MALICIOUS

PDF

71.7 KB Created: 2021-03-03 05:33:15 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-04-25
MD5: 74f52f6ab513d4cdb32d1bdaccef1078 SHA-1: 2a373e511f31b4927ca97d1042cf2d554e1d1199 SHA-256: 4dc98b87da1d85c0dc9a794f0cc0d8a618b52caf2762e74afda718f7d7b5b417
196 Risk Score

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • 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/award?keyword=how+to+write+quantitative+analysis PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4445754/normal_5fdc4f2d43b23.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4484356/normal_5fea042c47ebe.pdfIn PDF document text
    • https://vasinurevesodux.weebly.com/uploads/1/3/4/6/134605286/e305197.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366339/normal_6036b0efe7492.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4408987/normal_5ff0086ee3463.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4475391/normal_5fdc4bc90168e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4466680/normal_601981f644a03.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/pafiganovavi/dell_inspiron_530s_memory_specs.pdfIn PDF document text
    • https://s3.amazonaws.com/safago/58829506421.pdfIn PDF document text
    • https://s3.amazonaws.com/goviwigax/50737081578.pdfIn PDF document text
    • https://s3.amazonaws.com/padosumifubobo/inspection_chamber_installation_guide.pdfIn PDF document text
    • https://s3.amazonaws.com/tarizirefevifab/comparing_fractions_with_common_numerators_worksheet.pdfIn PDF document text
    • https://s3.amazonaws.com/wizitifowubux/marvellous_medicine_template.pdfIn PDF document text
    • https://s3.amazonaws.com/wovugi/97001063706.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_off0000dd75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD75 5020 bytes
SHA-256: 0cd03bd6b8800f0dc2801120bb77a487a789f06850d8feb294697a036418612a
font_01_sfnt_off0000eeb5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEB5 10360 bytes
SHA-256: 710c28490aebee917d9312a15c48e4c6ca5b6c05918f12c65f26fc050425d0dc