Malicious PDF — malware analysis report

Static analysis result for SHA-256 8397e551bcbda61d…

MALICIOUS

PDF

79.5 KB Created: 2021-09-12 14:48:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: b67e6c94c39fb29da1edd0e2a4c8d5d8 SHA-1: 924d5268e2f437e865e77dac5b0049687d62d3f5 SHA-256: 8397e551bcbda61dd9c9165f0395e62f7429b565593dc8423cccaf5e04082747
164 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. It also features a link farm pointing to compromised CMS upload storage and disposable hosting, suggesting an attempt to distribute further payloads or phish users. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 7

  • 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.
  • 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 https://infrive.ru/uplcv?utm_term=winds+of+steel+apk PDF link annotation
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/161384e5db52e1---torigo.pdfIn PDF document text
    • http://giadinhmedia.com/uploads/files/vobepasazefinofeles.pdfIn PDF document text
    • http://rm-centr.ru/uploads/file/nazipiroketususezila.pdfIn PDF document text
    • http://bonaparte-kerkrade.nl/fckeditor/ckfinder/userfiles/file/tileriminogariw.pdfIn PDF document text
    • https://holcom-wd.com/webroot/img/files/dajewetuxefejaman.pdfIn PDF document text
    • https://u-spot.biz/js/ckfinder/userfiles/files/jowisoxenoti.pdfIn PDF document text
    • https://cosmopolitanhotel.lastrada.bg/uploads/wysiwyg/files/nenusepoxepisixike.pdfIn PDF document text
    • http://htk2.altrodesign.eu/ckfinder/userfiles/files/belafukugabojudunajinow.pdfIn PDF document text
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/ceab78e74c533d9cfb229b55107b0c57/2523859151.pdfIn PDF document text
    • https://maftplayer.net/calisma2/files/uploads/jutamozejadudatufume.pdfIn PDF document text
    • https://tidurmalam2.com/contents/files/41709126453.pdfIn PDF document text
    • https://chilegastronomia.cl/uploads/userfiles/files/36448084384.pdfIn PDF document text
    • https://masterjobintl.com/ckfinder/userfiles/files/56933824439.pdfIn PDF document text
    • http://chanhbon.vn/media/ftp/file/38720429995.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/xupamanavuzuvoxofisov.pdfIn PDF document text
    • http://vincentianssjp.com/userfiles/file/90919079336.pdfIn PDF document text
    • http://bergepkolcsonzo.hu/userfiles/file/bulezisorivoji.pdfIn PDF document text
    • https://quangcaowebsite.xemlaco.com/uploads/files/tibafepekemaja.pdfIn PDF document text
    • https://sandp-engineering.com/ckfinder/userfiles/files/77636466146.pdfIn PDF document text
    • http://sm.ac.th/ckfinder/userfiles/files/84077080052.pdfIn PDF document text
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1612ebfb08a65d---56106091008.pdfIn PDF document text
    • http://cukrarnakolbaba.eu/obrazky/files/63528054930.pdfIn PDF document text
    • http://luxcottage.ru/stroykamen/userfiles/files/zufurazemamilaxatasola.pdfIn PDF document text
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/gg03gv3g2a12pqnj0qe2c30uup/zozupogowavafuxor.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_off0000ca6d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA6D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e284.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE284 10476 bytes
SHA-256: 081e43351dc81b7ae735d8c5472fa8d9e9dc2916339cd01b23aa63429aaef4a3
font_02_sfnt_off0000fa6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA6C 20808 bytes
SHA-256: 657c90baf10c154d4ac60cb275bf3fb65b8a68a12482b6f556dbc19596aa5932