Malicious PDF — malware analysis report

Static analysis result for SHA-256 ea1c84e4b70f7306…

MALICIOUS

PDF

76.5 KB Created: 2021-09-21 11:11:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 5c65f1e864ee22085207d647688c217c SHA-1: bb2fb1e285af400a06271c85ea3a090376162e7f SHA-256: ea1c84e4b70f73067d47620344a868f3075f1db8e95c1bca85f557caf0d47a82
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external URIs, many of which are part of a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded JavaScript is likely used to facilitate redirection to these malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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 https://medvor.ru/uplcv?utm_term=outlook+365+outgoing+mail+server PDF link annotation
    • http://pravkniga.ru/files/userfiles/files/48228421611.pdfIn PDF document text
    • https://www.domaine-vrignaud.com/ckfinder/userfiles/files/89578140613.pdfIn PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613dd6958d50b---14030301706.pdfIn PDF document text
    • https://kompaspt1.com/contents/files/48222374360.pdfIn PDF document text
    • http://konferencii.org/js/ckfinder/userfiles/files/7397657263.pdfIn PDF document text
    • http://radecznica.pl/userfiles/file/zowolano.pdfIn PDF document text
    • http://flomojapan.com/upload/files/piteradi.pdfIn PDF document text
    • https://tahitotfalu.hu/ckfinder/userfiles/files/vevusasot.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/zimigugetobolor.pdfIn PDF document text
    • http://mariondhuique-mayer.com/data/file/28100333068.pdfIn PDF document text
    • https://hsdinstruments.nl/uploads/files/3755160148.pdfIn PDF document text
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/n7mo7vopa082smejklejghhsu6/ruwovomito.pdfIn PDF document text
    • http://baldonimarcostudio.eu/userfiles/files/58279634189.pdfIn PDF document text
    • http://cu-hinothai.com/ckfinder/userfiles/files/danazamibuxokuvavogepan.pdfIn PDF document text
    • http://etcpremium.com/userfiles/files/sajofux.pdfIn PDF document text
    • https://xpress2.eu/ckfinder/userfiles/files/55318783078.pdfIn PDF document text
    • http://sm.ac.th/ckfinder/userfiles/files/pakosudujaludipetapafazu.pdfIn PDF document text
    • http://abwninemile.com/uploads/files/sufebaku.pdfIn PDF document text
    • http://miet-boot.ch/images/uploadedimages/file/6713560318.pdfIn PDF document text
    • http://mariondhuique-mayer.com/data/file/93199680674.pdfIn PDF document text
    • http://www.oomedia.com.tw/ckfinder/userfiles/files/jeguxepalanavina.pdfIn PDF document text
    • http://skisun.it/userfiles/files/15103500254.pdfIn PDF document text
    • http://sake-tori.com/images/library/File/kajoxibisakaduxavamidudit.pdfIn PDF document text
    • http://eltprof.ru/userfiles/file/7018895328.pdfIn PDF document text
    • http://gowowdeli.com/uploads/files/78123512193.pdfIn PDF document text
    • https://mimpishio2.net/contents/files/26230778911.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_off0000c57a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC57A 11208 bytes
SHA-256: cb688c9fa8dfc695578e3a9faa3d22cd715d48f405f7a182ef5198ed745e603a
font_01_sfnt_off0000dfcd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFCD 17024 bytes
SHA-256: 7fdb6217f3972786958392757a1d920b4d4687ff850eb44145d22a6aa341a2c9
font_02_sfnt_off00010c20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C20 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1