Malicious PDF — malware analysis report

Static analysis result for SHA-256 b71b3cd9f4ae0d83…

MALICIOUS

PDF

83.3 KB Created: 2021-09-12 08:32:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 8f71e020764eff56883ee08b644a22f7 SHA-1: 3104ab6615611d99f68a4136b54444ab571b9db1 SHA-256: b71b3cd9f4ae0d83e5a533a403e5aaddae1ec43df021bb8d840d4e3eea03e3ae
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs hosted on potentially compromised or disposable domains. These links are likely intended to lead victims to phishing sites or download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://drafthe.ru/uplcv?utm_term=mha+new+movie+2021 PDF link annotation
    • http://appli-veolia.net/ckfinder/userfiles/files/62799993451.pdfIn PDF document text
    • https://www.ftha.org/admin/ckfinder/userfiles/files/80172147553.pdfIn PDF document text
    • https://we-plus.tw/ckfinder/userfiles/files/24840672150.pdfIn PDF document text
    • https://luyenthitoeic.info/userfiles/file/9104985638.pdfIn PDF document text
    • https://vizzzio.ru/wp-content/plugins/super-forms/uploads/php/files/0fcd583c6c0fdfdfe8fbb10437a1d8c9/39928967245.pdfIn PDF document text
    • http://gongotour.com/FileData/ckfinder/files/20210905_35A76FF8958F4E78.pdfIn PDF document text
    • http://hnc2.com/userfiles/file/wojidipifokud.pdfIn PDF document text
    • http://cpk.by/ckfinder/userfiles/files/pojukazasituz.pdfIn PDF document text
    • http://kfoodntea.com/dataroom/file/bodezisirafajodixabowi.pdfIn PDF document text
    • http://daisytalavera.com/userfiles/files/68562744418.pdfIn PDF document text
    • https://jungleflightchiangmai.com/Uploads/files/25555266722.pdfIn PDF document text
    • http://jjkxmy.com/upload/files/202109111619272278.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/1613d3b7107aa5---61769452303.pdfIn PDF document text
    • https://militarynetwork.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613a78dbb307b---fepatiniwuwafo.pdfIn PDF document text
    • http://revucue.com/ckfinder/userfiles/files/bubetedovirimizejitulid.pdfIn PDF document text
    • http://1night2day.com/ckupload/files/jofosukosogivenutolifa.pdfIn PDF document text
    • https://egf.tw/test2/images/file/vefetujagawivi.pdfIn PDF document text
    • http://alphasigmaoverseas.com/userfiles/file/83672626989.pdfIn PDF document text
    • http://reversetheclocknow.com/ckfinder/userfiles/files/pukajidivixijises.pdfIn PDF document text
    • http://tachikawa-derma.biz/ckfinder/userfiles/files/bapepapesideso.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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e137.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE137 10400 bytes
SHA-256: 566ed8b0f5186aa6bc81df28c3370715d2cca61b35f2401d737bf3cd5e063e5b
font_01_sfnt_off0000f89f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF89F 18244 bytes
SHA-256: 306719aa821b826eb1661bd8a7cd4202da62cc1a5384ef7bcdb530da072c0bf3
font_02_sfnt_off000127c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127C9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1