Malicious PDF — malware analysis report

Static analysis result for SHA-256 91ddd49c11cd1fd6…

MALICIOUS

PDF

66.0 KB Created: 2021-03-03 18:56:43 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: 990337988946c09bd01b95ea03e31ce0 SHA-1: 08661fc56376ad1a8c2f00db702d595f2f079a64 SHA-256: 91ddd49c11cd1fd62056c74b6c5f4e10851bc8bf435387ee5cb97b941b29dbdf
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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.
  • 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://pelibifir.ru/strik?utm_term=commercial+beverage+cooler+for+sale PDF link annotation
    • http://rusherx.studio/how_to_clean_a_canvas_art_print1m9en.pdfIn PDF document text
    • https://rawubewo.weebly.com/uploads/1/3/1/4/131405976/pifimofe-falulilozikavu-ludepokixakamu-majalixozadeb.pdfIn PDF document text
    • https://nezuwiwobitedut.weebly.com/uploads/1/3/4/6/134600585/kosokuzeboxow_zejodisax_burakitojave.pdfIn PDF document text
    • https://zefinefan.weebly.com/uploads/1/3/2/8/132816158/tenabizakexulufire.pdfIn PDF document text
    • http://tabikola.online/is_there_a_navy_base_in_south_carolina60mnk.pdfIn PDF document text
    • https://cdn.sqhk.co/zefipuvuwifi/kijgfgd/genusenefofise.pdfIn PDF document text
    • https://kumenesasewoton.weebly.com/uploads/1/3/4/7/134773405/ravefunopuzon-xorexi-tabexesukonalok.pdfIn PDF document text
    • https://xigokujote.weebly.com/uploads/1/3/4/6/134649591/xujaluxulami.pdfIn PDF document text
    • https://jaxevilin.weebly.com/uploads/1/3/1/6/131606955/2140210.pdfIn PDF document text
    • http://sinakarazeg.22web.org/fl_studio_20_compatibility.pdfIn PDF document text
    • https://cdn.sqhk.co/rubalibuzodi/P3d6zjb/tractor_pull_fails_2017.pdfIn PDF document text
    • https://guzepebizosi.weebly.com/uploads/1/3/4/8/134880367/9410304.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://kexomuradalo.rf.gd/gunufugi.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_off0000c530.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC530 5304 bytes
SHA-256: 7d474d3ce1143b1c548d1a3524960203f22f8c61eaf246b2cfb67c6f0d747e0a
font_01_sfnt_off0000d72f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD72F 10712 bytes
SHA-256: 87e9633d0bdce0fce88eda77db1b8e568c7d3ac4a6c1b7b7c273aea623620e17