Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5015ed51b1d6768…

MALICIOUS

PDF

68.8 KB Created: 2021-01-19 17:59:20 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-15
MD5: d388e4f05c4f36801846c081b8ca368d SHA-1: 91d6682ef4b2a9a39c20e073bb87bb0c980749b2 SHA-256: b5015ed51b1d67681d405b261e3841a65ac6b617ac7536d4db37a3a525a82779
136 Risk Score

Malware Insights

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

The PDF file contains a high-confidence heuristic indicating it is a phishing lure, specifically using an SEO redirector. The embedded URL, https://leonvi.ru/aws?utm_term=adding+mixed+number+fractions+worksheet, is the primary indicator of this malicious activity. While no scripts were explicitly extracted, the PDF structure and the nature of the URL suggest a phishing attempt designed to trick users into downloading a malicious file or visiting a compromised site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://leonvi.ru/aws?utm_term=adding+mixed+number+fractions+worksheet PDF link annotation
    • https://cdn.sqhk.co/xawodoze/iB4hhid/dragon_racer_2.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4473892/normal_5fe2a4e4383fd.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4421629/normal_5fdc4ed2b55b1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489588/normal_5faa7b33565ee.pdfIn PDF document text
    • https://cdn.sqhk.co/mofekuma/Tgcf3sg/vice_news_breonna_taylor.pdfIn PDF document text
    • https://cdn.sqhk.co/kefesizo/RZWqia6/project_manager_jobs_mankato_mn.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4366668/normal_5fe1a29dea9ee.pdfIn PDF document text
    • http://xitigedomure.66ghz.com/bluestacks_3_for_windows_10_pc.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/labitajaxatufib/update_android_auto_manually.pdfIn PDF document text
    • http://regujivabi.rf.gd/kotizazegigakex.pdfIn PDF document text
    • http://notaruk.rf.gd/biodata_format_with_photo.pdfIn PDF document text
    • https://s3.amazonaws.com/rozebofukixus/31975747545.pdfIn PDF document text
    • http://wigazimo.epizy.com/ariston_gas_boiler_service_manual.pdfIn PDF document text
    • https://s3.amazonaws.com/jodabiladezot/handmade_foam_sheet_flowers.pdfIn PDF document text
    • https://s3.amazonaws.com/dugibabafod/pesufasanoxefuxuved.pdfIn PDF document text
    • https://s3.amazonaws.com/bomupi/pathogenesis_of_viral_hemorrhagic_fever.pdfIn PDF document text
    • http://latilofu.rf.gd/delay_and_sum_beamforming_using_matlab.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_off0000d0c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0C6 5756 bytes
SHA-256: 7d2a2ce3dd749fd44ad2e65a427a73dd0333780128f23445a5f89e3163aba7a1
font_01_sfnt_off0000e44f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE44F 9944 bytes
SHA-256: 4513d2999b0db13b3ec88af5082895169e2c19a1ca706d270c16c47520eeec1c