Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f7e94045c108da7…

MALICIOUS

PDF

81.3 KB Created: 2021-09-09 20:26:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 9ad884b96aa7e103b8c32afe03919bc1 SHA-1: 17780d7bafa56b6e6f16c2141e059c68d9d42978 SHA-256: 5f7e94045c108da749014ab99363fa67b3e42e827834d2d69f594472d3497e52
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, and exhibits characteristics of a link farm PDF. It contains numerous embedded URLs pointing to external PDF files, suggesting an attempt to redirect users to malicious content. While no scripts were explicitly extracted, the PDF structure and heuristic firings indicate a malicious intent to host or link to harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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
  • 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 http://bzws.zhanyougame.com/ckfinder/userfiles/files/gugexisozor.pdf In PDF document text
    • http://sdsenlex.com/upload/files/94921145538.pdfIn PDF document text
    • https://farmaciasacoor.com/site/upload/file/32661380340.pdfIn PDF document text
    • http://coreaad.com/DreamDataUpload/file/10555493095.pdfIn PDF document text
    • http://thienthaopc.com/upload/FCK/file/17627700031.pdfIn PDF document text
    • http://csc025.com/userfiles/file/20210903225615_g9blud.pdfIn PDF document text
    • http://trevelci.ru/ckfinder/userfiles/files/kinaku.pdfIn PDF document text
    • http://www.cpiequipos.com/assets/images/user_files/files/24656846500.pdfIn PDF document text
    • https://agriplan-rs.com/dados/ckfinder/files/86440629212.pdfIn PDF document text
    • https://a-guskov.ru/uploads/files/gofidufosu.pdfIn PDF document text
    • https://acrgruppe.de/userfiles/file/luvulu.pdfIn PDF document text
    • https://sunwayhk.com/louis/STARKGROUP/ckfinder/userfiles/files/romisuzo.pdfIn PDF document text
    • https://kuzeyilac.com/resimler/files/66340095844.pdfIn PDF document text
    • https://solucionaesp.com/ckfinder/userfiles/files/66181118537.pdfIn PDF document text
    • http://chongthamnguoc.vn/img/files/vunovikomovufiluvipiretul.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137fe02abfad---6962975909.pdfIn PDF document text
    • http://thaisomboonautopart.com/userfiles/files/sudizorikigex.pdfIn PDF document text
    • http://mislenyiallatorvos.hu/userfiles/file/17674330677.pdfIn PDF document text
    • http://heureka-cz.eu/files/96000054854.pdfIn PDF document text
    • http://ljhalls.com/wp-content/plugins/super-forms/uploads/php/files/3bd82b57b90dc1384c2edc6d8a51f637/nizokijeza.pdfIn PDF document text
    • https://thehouseproduction.net/file/gufemajogaf.pdfIn PDF document text
    • https://bucatariizidite.ro/printuri-fi/files/fejojetejituloveso.pdfIn PDF document text
    • https://adrfarysz.pl/userfiles/file/10635738236.pdfIn PDF document text
    • http://signauction.net/userfiles/file/noxogovumikenamaxo.pdfIn PDF document text
    • https://sayurhijau.com/contents/files/tuguko.pdfIn PDF document text
    • http://instant-image.net/UserFiles/Site/File/kojadopizurobuxuroxo.pdfIn PDF document text
    • http://webcertain.ca/contentupload/fckeditorUploads/organization_/file/kafudomarurulolaw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=convert+csv+to+vcf+androidPDF link annotation
    • 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_off0000d9ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9FF 17440 bytes
SHA-256: 288e350915dce0f67d2cb153557b65f1482542cb4207eabb133317b213dbe633
font_01_sfnt_off000106cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106CF 10520 bytes
SHA-256: a453de1419dff8c52a0b04ea3c677f2e91cbdbc4bf37b0ca8f6a8bc4a298aa48
font_02_sfnt_off00011efb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EFB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1