Malicious PDF — malware analysis report

Static analysis result for SHA-256 e4c71e013bf60224…

MALICIOUS

PDF

87.4 KB Created: 2021-03-20 21:18:52 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: 9c48631272d6372523f2016618521c9c SHA-1: 21b031e03a06b2ece251351d75f73534ad4f5c09 SHA-256: e4c71e013bf60224935b4363d39f7321d66a88b032a8b780bdb698b33b98e4f3
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many hosted on disposable domains, suggesting a link farm or phishing operation. The presence of a ClamAV detection for 'Pdf.Phishing.Trojan' and ML classification further supports malicious intent. While no scripts were explicitly extracted, the heuristic firings indicate the PDF is designed to redirect users to potentially malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://zajinet.ru/award?keyword=rscit+application+form+2020+pdf PDF link annotation
    • https://cdn.sqhk.co/jotepomi/giQWdQp/mixed_messages_synonyms_list.pdfIn PDF document text
    • http://zonetufe.iblogger.org/rikaz.pdfIn PDF document text
    • https://pinozawekik.weebly.com/uploads/1/3/4/5/134589254/gexuwiv_xutuda_peripelebo_wonolefofogem.pdfIn PDF document text
    • https://cdn.sqhk.co/jilebodetifa/agEjgkb/94914853334.pdfIn PDF document text
    • https://kepefiporewe.weebly.com/uploads/1/3/4/7/134704647/wusak.pdfIn PDF document text
    • https://doruvovet.weebly.com/uploads/1/3/2/7/132740873/7774576.pdfIn PDF document text
    • https://zepudelewow.weebly.com/uploads/1/3/2/6/132682561/tisomi_dolezemig_nomaxajuk.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://favifodov.rf.gd/beef_stew_recipes_with_pictures.pdfIn PDF document text
    • https://s3.amazonaws.com/gapuruxumeg/94338101746.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/913a6bdd-eb7f-4a7c-a662-2a08eb6e7965/ts_420_stihl_cutquik_for_sale.pdfIn PDF document text
    • https://s3.amazonaws.com/vidadaviwal/fojerelukarikepuzo.pdfIn PDF document text
    • https://3fb740b9-71d8-4183-8edb-de11b68c0a29.filesusr.com/ugd/1fbf8b_a5d68db56ef641009c0787be813449c1.pdf?index=trueIn PDF document text
    • https://74f55dc1-c9a5-4be3-8cb6-5a41d2e6c5ca.filesusr.com/ugd/bacb18_e0647cf0c61643e8bddd8bd555e8590e.pdf?index=trueIn PDF document text
    • https://8f1ef4f7-3f23-41ef-a3d6-4e5873a175a2.filesusr.com/ugd/d318ce_fd90045838ce455ebdfd8d0ba3977120.pdf?index=trueIn PDF document text
    • https://9a4203bb-6ff2-4ef1-9c63-3f113f84a884.filesusr.com/ugd/ea9bdf_7b38b2fb0b504988a6f354d4f88b749c.pdf?index=trueIn PDF document text
    • https://e437b920-fa79-41d5-b67c-0ca059f4e77a.filesusr.com/ugd/d97c10_33903ed1dd0a4099ad52044678fb0819.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/365bc6af-ddbe-4cf0-adf8-f83488a4952e/minn_kota_riptide_sf_80_parts.pdfIn PDF document text
    • https://s3.amazonaws.com/waxapoz/lowanufoteminuruwiradu.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010202.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10202 5580 bytes
SHA-256: ea637b6f48f385ae7cac1adc615862c4cba1a30b012f5b3140da005968b77c28
font_01_sfnt_off000114ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114EA 10944 bytes
SHA-256: f6164a0c3e448f6d26ff340047bbf59aa4624c18cb2badf68c4946509337ea2b
font_02_sfnt_off00013a5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A5C 16204 bytes
SHA-256: 867fbc1df4d1fedfc3319e8cff6afbf5f916a5f96dfa7427f1124696c565883f