Malicious PDF — malware analysis report

Static analysis result for SHA-256 338bfbef9875ff2a…

MALICIOUS

PDF

71.4 KB Created: 2021-03-08 17:05:30 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-22
MD5: 4aa853ef95efaecaade42124d8189268 SHA-1: ce3285e4bdd04183198a70fc729f368b6c3d68c7 SHA-256: 338bfbef9875ff2a118287602a1dd3a3e84dbec105e78f722c62091be3f67130
186 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ClamAV and an ML classifier, exhibiting characteristics of a link farm. It contains numerous external URIs, with a significant number pointing to disposable hosting, suggesting an attempt to manipulate search engine results or distribute potentially harmful content. The primary attack pattern involves directing users to a large number of external PDF files, likely for SEO spam or as a distribution mechanism for further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://xajibur.ru/award?keyword=benzoilmetronidazol+ems+bula+pdf PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4459479/normal_5fcc9edee77c2.pdfIn PDF document text
    • http://weareanonymous.org/gebojapa1qxpm.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4479679/normal_603de888312fe.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4527357/normal_5fd1f815caed5.pdfIn PDF document text
    • http://poverkavoda.website/dopojojelujilinlusc.pdfIn PDF document text
    • http://help-nanny.site/spongebob_wallpaper_freezykqa.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4383804/normal_5ff2ab33a641a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4365626/normal_6038685dedf3c.pdfIn PDF document text
    • http://lozuzaragujeb.mypressonline.com/does_garmin_have_black_friday_sales.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489440/normal_604203a69ae25.pdfIn PDF document text
    • https://dijibelusubif.weebly.com/uploads/1/3/4/8/134871127/1303adceb3112.pdfIn PDF document text
    • http://kushtanash.ru/3082752568pg06h.pdfIn PDF document text
    • http://zaxevef.getenjoyment.net/apc_back-ups_es_550_owners_manual.pdfIn PDF document text
    • https://tekovidekugowi.weebly.com/uploads/1/3/5/3/135315876/lideziroxe-buvezupigeneno.pdfIn PDF document text
    • http://midikakuvekume.mywebcommunity.org/59619220658.pdfIn PDF document text
    • https://gozerezujokosas.weebly.com/uploads/1/3/4/8/134856803/segedinekiwugirob.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4459034/normal_6041911a17089.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4421613/normal_60153de0dd34d.pdfIn PDF document text
    • http://bhd-management.space/jexukimeza3jzjo.pdfIn PDF document text
    • http://nupewijanetari.medianewsonline.com/hebrew_dictionary_and_thesaurus.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4390052/normal_5fc90fb491754.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/d016d820-cdb1-4963-8ffe-540f3922d5f1/73836312646.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/492bf258-e09e-42c0-af9d-ba03f4c70f80/zuderilulatixisoxapar.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6c866f82-7e6b-4d8f-bed6-959e93e9f04b/how_to_download_sound_drivers_for_windows_8.1.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4b536d3e-9e7a-4b54-bd32-b070df9378ae/livepuwiwejuvojatazawi.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_off0000d970.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD970 5428 bytes
SHA-256: b597bb53d75f96322c73070a127a205471595f5d2154d0f0f3f1aa429aacf414
font_01_sfnt_off0000ebcd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBCD 10552 bytes
SHA-256: 80ee40ef3de7e1678a06e9e06e237c6f97ffc5bd2bc66db56848d61648e33f77