Malicious PDF — malware analysis report

Static analysis result for SHA-256 571c4e8441635ef8…

MALICIOUS

PDF

92.0 KB Created: 2021-04-09 12:01:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: fb159d859959671c8ac5e724b4b3c691 SHA-1: ad4a13c8e58b1a65143cb8eb77b1ac12e9296522 SHA-256: 571c4e8441635ef85a20cf164e52228dc0e02a292ea0c97fb05a00e3dd6437c1
196 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a phishing or malware distribution attempt. It contains a mass of external links, many of which are SEO redirectors, suggesting an attempt to drive traffic to malicious sites. The primary suspicious URL identified is https://kuzutuzo.ru/strik?utm_term=art+history+major+salary, which is likely part of a phishing or malware delivery chain.

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.
  • 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.
  • 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://kuzutuzo.ru/strik?utm_term=art+history+major+salary PDF link annotation
    • http://maewallace.com/sushi_neko_restaurant_okc7kygo.pdfIn PDF document text
    • https://cdn.sqhk.co/lokutibu/jdj0Jii/zombs._io_battle_royale_download.pdfIn PDF document text
    • https://cdn.sqhk.co/kaxonavi/8DeOSiP/download_gangster_squad_origins_mod.pdfIn PDF document text
    • http://pokypka.xyz/barisal_district_mapult6q.pdfIn PDF document text
    • https://cdn.sqhk.co/kolokejo/aogiagj/crazy_pumpkins_ideas.pdfIn PDF document text
    • https://cdn.sqhk.co/lisesemafo/bjbjfgc/jipurin.pdfIn PDF document text
    • https://cdn.sqhk.co/sepexapubu/o00JRaA/90585677867.pdfIn PDF document text
    • https://cdn.sqhk.co/migawudewiw/hgGSqje/synonyms_and_antonyms_definition.pdfIn PDF document text
    • http://idealicait.website/what_is_the_command_to_list_all_files_in_a_directoryljui2.pdfIn PDF document text
    • http://monstergym.ru/15979026421og4uc.pdfIn PDF document text
    • https://cdn.sqhk.co/ludozenidi/EIhbjfV/aarp_insurance_life.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/xukonakefules/sample_eeo_report_component_2.pdfIn PDF document text
    • https://60ceb029-6f78-4d42-8ea4-15ca08d8077a.filesusr.com/ugd/857e61_037f677093254e10a22d2be2df5e4f90.pdf?index=trueIn PDF document text
    • https://b7c0b8aa-2746-4b81-86ab-4dfcec723e12.filesusr.com/ugd/383078_82cafc740be44a5398ec2fdaa349c46e.pdf?index=trueIn PDF document text
    • https://8dac4d01-2cd1-45d2-8b5f-6005f802adc9.filesusr.com/ugd/1f96ce_dbcdf94ac1fc4869b205608510fb7810.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/napoledunadigo/46755435910.pdfIn PDF document text
    • https://s3.amazonaws.com/juzinaramip/decision_tree_analysis_template.pdfIn PDF document text
    • https://s3.amazonaws.com/zinudipir/34299673368.pdfIn PDF document text
    • https://s3.amazonaws.com/wexukufedepim/36036974168.pdfIn PDF document text
    • https://s3.amazonaws.com/jaxesabi/descriptive_writing_worksheets_grade_4.pdfIn PDF document text
    • https://972af30b-04c2-4618-b911-83ba0b7fef9e.filesusr.com/ugd/84a5c6_9e6726f4064544a88792e3cf6fa96a2c.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/ropidadegaxut/moxuwosonamoxosijogenu.pdfIn PDF document text
    • https://s3.amazonaws.com/visagogijulep/nephrotic_syndrome_relapse_guidelines.pdfIn PDF document text
    • https://s3.amazonaws.com/xulepiwa/admission_form_format_for_coaching_classes_word.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_off00012be6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BE6 5092 bytes
SHA-256: 87d30290902b639dd5700276c11fd2941b6ec7f001d1be3ba17fc147465cbacd
font_01_sfnt_off00013d16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D16 11024 bytes
SHA-256: af718ac99c41684380311a8aa12665fc6b91adff3d6330aa48557907f1156570