Malicious PDF — malware analysis report

Static analysis result for SHA-256 9b8c8600ad78f1db…

MALICIOUS

PDF

72.1 KB Created: 2021-09-24 15:29:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: f885be1bfe8a114cfd94b7059804fbff SHA-1: 15c1b4a4fc9a0a62372c7a923f10d5d94486ce04 SHA-256: 9b8c8600ad78f1dbc85736eb24795fea4dedac54bdcd0a595f4c2798e21aa375
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file detected as malicious by ClamAV and an ML classifier. It contains embedded JavaScript and numerous external links, some pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution attempt. The presence of embedded JavaScript indicates an attempt to execute code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 http://pantanalmsnews.com.br/ckfinder/userfiles/files/vizulisirixepiwavewir.pdf In PDF document text
    • https://apaman.ti-am.jp/js/ckfinder/userfiles/files/zefajitiwepasagetefepe.pdfIn PDF document text
    • http://thietbimaugiao.vn/Images_upload/files/8822762297.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130d11a0dd8a---luvirotereludegilebuw.pdfIn PDF document text
    • https://worldpigment.com/image/upload/File/dalasabatowasetulok.pdfIn PDF document text
    • http://perseverance.cyou/updatefiles/file/8798881771.pdfIn PDF document text
    • http://crestviewshopping.abwingsmd.com/uploads/files/luravava.pdfIn PDF document text
    • http://xedaptap.net/userfiles/file/fevomewodoxunifad.pdfIn PDF document text
    • http://imaginove.eu/data/Files/lejisepizexopewaz.pdfIn PDF document text
    • https://preprodpcb.com/userfiles/files/nutut.pdfIn PDF document text
    • http://reanda.com/jingkelun/userfiles/files/20210906210317.pdfIn PDF document text
    • http://sovaimm.it/userfiles/files/zalav.pdfIn PDF document text
    • http://321eastern-thailand.com/userfiles/files/54294523306.pdfIn PDF document text
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/efd8acc4d5ef0aace9da417f209106cd/gomedifaxipevobiderosip.pdfIn PDF document text
    • http://hastensandbreakfast.nl/userfiles/file/xejadenozakokopigud.pdfIn PDF document text
    • https://virtualpulse.eu/UserFiles/file/katogudonetoxigaz.pdfIn PDF document text
    • http://www.serenissimaservizi.com/files/1608898505.pdfIn PDF document text
    • https://cometsecurity.in/admin/userfiles/file/1393089146.pdfIn PDF document text
    • http://meskerjager.nl/media/files/48122312520.pdfIn PDF document text
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e288a9cf32---kogejesesuke.pdfIn PDF document text
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613f9fed49cfe---buzaruxowejosavuzitofi.pdfIn PDF document text
    • http://dakmoto.cz/obrazky/file/xagukezazufufoded.pdfIn PDF document text
    • https://dormet.eu/web/uploads/files/simezoxojajur.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=unblock+me+premium+apkPDF 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_off0000b161.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB161 18632 bytes
SHA-256: c18fd6ceb0dcb4e17a8f7785665afcefbc83fc9b85ab1f3d5f9285a8be5b612a
font_01_sfnt_off0000e1ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1AD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f9c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9C4 10608 bytes
SHA-256: e1e3f94ff2962810addf84bb22063ac2cd953c066491de4cd75c8c2da9e94a8a