Malicious PDF — malware analysis report

Static analysis result for SHA-256 82bbcc4ec8bb2ef7…

MALICIOUS

PDF

72.6 KB Created: 2021-03-23 11:35:27 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 5c97e273137fc945420b6a419122b703 SHA-1: 03265bdc45798b80849ec3e7756dbb68854ec855 SHA-256: 82bbcc4ec8bb2ef72faa528c0d3695b588756bfa5317335b4a02bdd799a55109
254 Risk Score

Malware Insights

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

The PDF contains a deceptive title and numerous links, many of which point to redirector infrastructure designed to lead users to malicious sites. Heuristics indicate this is a link farm for SEO phishing, and the primary redirector URL is associated with known malicious activity. While no scripts were explicitly extracted, the PDF structure and link farm behavior strongly suggest an attempt to distribute malware or conduct phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://yafferge.ru/123?utm_term=alphabet+coloring+worksheets+for+3+year+olds In PDF document text
    • https://cdn.sqhk.co/gejemizus/fphbMsj/100_bundt_cake_recipes_australia.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4412415/normal_5fe7dc6b5f9f2.pdfIn PDF document text
    • https://cdn.sqhk.co/zabitokepum/hhgihgg/remibaruwawudefadosijewif.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4449776/normal_6041919aeb713.pdfIn PDF document text
    • https://cdn.sqhk.co/demexadol/ergdBku/56264669293.pdfIn PDF document text
    • https://cdn.sqhk.co/koluvukirate/chepCji/penedolugojamefonega.pdfIn PDF document text
    • https://cdn.sqhk.co/vulovosovem/hfhieAZ/best_sudoku_online_games.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489255/normal_6041632b2c2d5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4403428/normal_6035f24668e60.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4485711/normal_605263bd2f75a.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/zarusegibitumet/xageraw.pdfIn PDF document text
    • https://s3.amazonaws.com/wovugi/xugiborifeko.pdfIn PDF document text
    • https://cccd2283-d272-450a-840b-6541230ebad2.filesusr.com/ugd/5de1df_c18347d9f91149a589cd6ef565ed668c.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/fulosobezur/what_to_say_in_an_interview_for_medical_assistant.pdfIn PDF document text
    • https://s3.amazonaws.com/najubu/file_in_browser_typescript.pdfIn PDF document text
    • https://cc67bef4-e22e-42fd-bf01-3f02b15f800b.filesusr.com/ugd/080020_16d47d349a9c44fe97cf5319d5df0254.pdf?index=trueIn PDF document text
    • https://2703069b-a6ff-4ff9-983c-db139a8d76ba.filesusr.com/ugd/8b61cf_03195d9a9da34960ba921dce87860c3a.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/towutoginadivu/20393319869.pdfIn PDF document text
    • https://s3.amazonaws.com/dogazisuze/kewukebaludadowemejubasuw.pdfIn PDF document text
    • https://s3.amazonaws.com/lupuvogotog/tupapasitomiter.pdfIn PDF document text
    • https://s3.amazonaws.com/kewuxejikiwe/xepebumifavavozivididijeg.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_off0000dbe6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBE6 5968 bytes
SHA-256: 47269599100fc50565301438ecd48d3f0a83c517a8af6ebad4e60ceb6a950d88
font_01_sfnt_off0000f043.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF043 10628 bytes
SHA-256: 750b5f1c327b08c333a9620f45d8ee695c6ad0fcfdb666914afe460dbf7f4a2f