Malicious PDF — malware analysis report

Static analysis result for SHA-256 19b1e09e4a753227…

MALICIOUS

PDF

72.5 KB Created: 2021-05-02 17:41:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-13
MD5: ba83679b0e36729f9909f4a55bd61b8d SHA-1: 74239f4796c17234186be2f2df1718d3deaf8c69 SHA-256: 19b1e09e4a753227c714e5d403218472552be503a50fed668968f58d649ccef5
186 Risk Score

Malware Insights

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

The sample is a PDF file identified as malicious by ClamAV and an ML classifier. It contains a large number of external links, many pointing to disposable hosting, suggesting a link farm or SEO manipulation tactic. The presence of embedded URLs and the PDF_SEO_LINK_FARM heuristic indicate a primary function of redirecting users to other content. While no scripts were explicitly extracted, the PDF format can embed JavaScript, and the heuristic PDF_SEO_LINK_FARM suggests a potential for malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://druttle.ru/strik?utm_term=10000+reasons+chords+capo PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4416140/normal_606adff825084.pdfIn PDF document text
    • http://kind-insta.site/the_armor_of_god_priscilla_shirer_free9hw45.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4483870/normal_6037381549020.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4470387/normal_6044cef2bc5ab.pdfIn PDF document text
    • http://shoop-ft.ru/tesurasusjwnlw.pdfIn PDF document text
    • http://unlockdeals.shop/how_do_i_join_network_marketingz8l1z.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4495244/normal_6036933b7d9c4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4410186/normal_602cfd7d7f664.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4424662/normal_606bc1067f441.pdfIn PDF document text
    • http://cardioactiveitalia.site/11414441666j0rp6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370057/normal_6066774cd1996.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4473322/normal_601eec5cec261.pdfIn PDF document text
    • http://motarojetox.sportsontheweb.net/best_ios_app_for_annotation.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4465259/normal_5fd0507456ac0.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/mozirolinitaje/molew.pdfIn PDF document text
    • https://e0f910ba-f4aa-4d6b-87f6-24d78cda99ab.filesusr.com/ugd/cc15ef_1cc868918973434ca6e4c3c085a72c1a.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/fisulefajow/cognitive_dissonance_worksheets.pdfIn PDF document text
    • https://s3.amazonaws.com/xopugup/wafuxowo.pdfIn PDF document text
    • https://s3.amazonaws.com/kovilowab/tesojirofibafadizu.pdfIn PDF document text
    • https://s3.amazonaws.com/lopadivupudexa/satonazubajananodujebiwop.pdfIn PDF document text
    • http://vizozaforuf.atwebpages.com/gre_verbal_reasoning_practice_test.pdfIn PDF document text
    • https://1350f94c-8d6f-42b4-8351-24983ad6a49a.filesusr.com/ugd/4aae87_153b6c9fd1dc4cb1957711340aea729a.pdf?index=trueIn PDF document text
    • http://ropupifalapoges.atwebpages.com/wopemim.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_off0000dc5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC5F 5228 bytes
SHA-256: 12abfc9903202faa032104359d841a713b2255fb603870128d49b847d1b1fa83
font_01_sfnt_off0000ee21.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE21 11312 bytes
SHA-256: 4176c13839b30d6033639c0112a425ac5e90e67a2d80e0d1e370cf9ab585386b