Malicious PDF — malware analysis report

Static analysis result for SHA-256 9fa9a53d799546f9…

MALICIOUS

PDF

70.1 KB Created: 2021-10-03 02:44:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 5697ac1416efd9f2a9442eac789fed28 SHA-1: e546ff1005f94ad26f46df4f261c4f2456e6ca17 SHA-256: 9fa9a53d799546f995f96f21789940af47af2eff8858177f7865f830b8437437
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code within documents. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the document is designed to host numerous links, likely leading to malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, with the embedded JavaScript likely responsible for redirecting the user to external URLs such as http://zavalinka.by/var/upload/file/zomutivafaw.pdf.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://zavalinka.by/var/upload/file/zomutivafaw.pdf In PDF document text
    • https://hanakspotrebice.cz/eshop/ckfinder/userfiles/files/matija.pdfIn PDF document text
    • https://signatureshreyas.in/userfiles/file/45449467856.pdfIn PDF document text
    • http://ihanzao.com/userfiles/file/20210920124634_1308147405.pdfIn PDF document text
    • http://explosivedevices.ru/media/file/buwix.pdfIn PDF document text
    • http://juncheng.tw/upload/files/zudusibovozaratovigek.pdfIn PDF document text
    • http://keletunderground.hu/images/uploaded_pics/file/kalemazofijovusuxupome.pdfIn PDF document text
    • https://kme.pl/global/app/webroot/uploads/file/16304680030969.pdfIn PDF document text
    • http://progettogeometra.it/userfiles/files/kafetivusofasesasulaf.pdfIn PDF document text
    • http://internet-trade.cz/UserFiles/file/72542166481.pdfIn PDF document text
    • http://finsura-lifedirect.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16158d569ad903---64759094165.pdfIn PDF document text
    • https://dailyhondaotomientay.com/upload/files/zowukuteloginapisuvux.pdfIn PDF document text
    • http://1night2day.com/ckupload/files/vudifezekesofexib.pdfIn PDF document text
    • http://iaestedresden.de/userfiles/file/35217875074.pdfIn PDF document text
    • https://ataru.site/js/ckfinder/userfiles/files/rifakufexozogigulejowati.pdfIn PDF document text
    • http://www.julietlandau.com/fckeditor/userfiles/file/98466048388.pdfIn PDF document text
    • http://anquocrealty.com/uploads/image/files/vuliloguduvaz.pdfIn PDF document text
    • http://ride-on-earth.com/images/blog/file/68258259703.pdfIn PDF document text
    • http://manisafar.com/basefile/marcosafarir/files/18760110868.pdfIn PDF document text
    • http://bienbao.org/uploads/files/zemasojivuva.pdfIn PDF document text
    • http://tangiahoang.vn/Images_upload/files/rumas.pdfIn PDF document text
    • http://mygotour.com/FileData/ckfinder/files/20210922_F60B052F941D85B1.pdfIn PDF document text
    • https://ph2020.org/FCKeditor/file/79728071017.pdfIn PDF document text
    • https://istanajp.com/contents/files/8562958265.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=the+big+questions+a+short+introduction+to+philosophy+pdfPDF 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_off0000b051.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB051 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c868.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC868 11364 bytes
SHA-256: 20a6507318a4bb96b6398081deaa5cfafcdf855718ab54622ad168890d2a9280
font_02_sfnt_off0000e260.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE260 15788 bytes
SHA-256: 1b9bc41c81b8bf8f5a1e94b0ddb05a5998cc7e4746a4949bc48aee4a96314761