Malicious PDF — malware analysis report

Static analysis result for SHA-256 657ac58dfa19e639…

MALICIOUS

PDF

86.4 KB Created: 2021-09-12 06:37:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 63e2b48dbb804a511e7a23ee20269eb2 SHA-1: 4812ff0c1294cc4174a3bf558b097bc53c0d766d SHA-256: 657ac58dfa19e639001d57e512668a8304f98f94e5ee838e2b2120a9981c1c6e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

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, hosting numerous external URIs across various domains. While no scripts were explicitly extracted, the PDF structure and the presence of many external links suggest an attempt to redirect users to potentially malicious sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • 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.
  • 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://residenciasanamaro.es/userfiles/files/xuworejefurogiza.pdf In PDF document text
    • http://iwilldoit.ru/uploads/files/files/56833587678.pdfIn PDF document text
    • http://www.perchegouet.com/ckfinder/userfiles/files/pitux.pdfIn PDF document text
    • https://berbagiangka.com/contents/files/13955524750.pdfIn PDF document text
    • https://flavio-tonon.it/public/file/30472216051.pdfIn PDF document text
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/161354cae3c6cc---dulowinopokuvifedip.pdfIn PDF document text
    • http://lhdrum.com/User_File/UpFile/file/20210912032217_YmVqaWdveG9waXhpcmltZXhvcGVuZWQ=.pdfIn PDF document text
    • http://chroscina.com/userfiles/file/bililozovafutitajuwedoni.pdfIn PDF document text
    • https://www.champagne-cornevin.fr/ckfinder/userfiles/files/54150822933.pdfIn PDF document text
    • http://srs-budapest.hu/uploads/files/38264695641.pdfIn PDF document text
    • http://gfzgt.ch/upload/file/63173449875.pdfIn PDF document text
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/8vb88q26eu55bb2ue6sru9fq75/13912264938.pdfIn PDF document text
    • http://umrllc.com/userfiles/files/sadexapopiw.pdfIn PDF document text
    • http://allivecoat.com/userData/board/file/tigenapugu.pdfIn PDF document text
    • http://kelakewangshangduchang.a9188.com/upload_files/art_files/files/20210904_123803.pdfIn PDF document text
    • https://ndmoyun.com/calisma2/files/uploads/kamepelokejirufa.pdfIn PDF document text
    • http://livestocktool.com/d/files/vobutisabidurubeturirewes.pdfIn PDF document text
    • http://jiuxingchaoshi.com/uploads/file/042102481662.pdfIn PDF document text
    • http://dream-mebel.com/pic/file/kefuxesubekozogifuwoboten.pdfIn PDF document text
    • http://greenearthgardens.org/userfiles/80398834595.pdfIn PDF document text
    • http://itcbeautytrainingschool.com/userfiles/file/bijajozovak.pdfIn PDF document text
    • http://ecolservizinettuno.com/userfiles/files/43361245506.pdfIn PDF document text
    • https://strategie-forex.com/ckfinder/userfiles/files/70686330052.pdfIn PDF document text
    • http://tiendanatacion.com/noticias/files/8081834844.pdfIn PDF document text
    • https://schmitz.cz/res/file/25806980991.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=icons+top+right+corner+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_off0000ea24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA24 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001023b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1023B 10700 bytes
SHA-256: 0ab90d3a98fb69f1ac0bac2b57fdc922131c2420e8e55ead04f2fb9e3cbdabfe
font_02_sfnt_off00011a84.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A84 18900 bytes
SHA-256: 6512a3bcab3ceebf10af645980b5db7a1276394e8d7e3e885222d830953fed73