Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b9e66d097a93900…

MALICIOUS

PDF

75.9 KB Created: 2021-09-19 00:14:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 442b08ef62b581807b2cba8483566c50 SHA-1: 332da15281ad87914ab5f0a50146d2eecf58c589 SHA-256: 3b9e66d097a9390096da8117b6d417512bea4619c2e9ccaecfee373333771ca8
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and an ML classifier, with a critical heuristic firing for PDF_JS indicating embedded JavaScript. The PDF also exhibits characteristics of a link farm, with numerous external URIs pointing to potentially malicious content. The embedded JavaScript likely serves to execute malicious code or redirect the user, contributing to a phishing or malware distribution attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://www.xcelsus.de/wp-content/plugins/formcraft/file-upload/server/content/files/16143bd67c074d---14204655764.pdf In PDF document text
    • https://gs-hemeringen.de/ablage/userfiles/files/48393825318.pdfIn PDF document text
    • http://circolonauticofavignana.it/userfiles/files/68394437389.pdfIn PDF document text
    • http://laiyi-art.com/userfiles/file/28314069963.pdfIn PDF document text
    • https://jbdclothiers.net/emailer/userfiles/file/2477823261.pdfIn PDF document text
    • http://veterinariomauracotti.it/userfiles/files/wanowodafekevafo.pdfIn PDF document text
    • http://margheritango.it/userfiles/file/netilusolemupopiwumisufol.pdfIn PDF document text
    • http://coniperfumes.cl/js/ckfinder/userfiles/files/65523879526.pdfIn PDF document text
    • http://theleadershipworks.com/PO2/UPFILE/userfiles/files/sefub.pdfIn PDF document text
    • https://kurek-rowery.pl/user_pict/file/sezexekosusavoxuriv.pdfIn PDF document text
    • https://nevjegyzek.eu/uploads/file/safebudumepudivamipa.pdfIn PDF document text
    • https://www.fangjin.org/ckfinder/userfiles/files/wubugubusezideguzifa.pdfIn PDF document text
    • http://igs.compcierge-asia.com/ckfinder/userfiles/files/belenafapepuperotepuzoxe.pdfIn PDF document text
    • https://history.tlshaa.org.tw/ckfinder/userfiles/files/dagaveragoj.pdfIn PDF document text
    • http://xn--80aadcnaeutgftohcogh8i8dsc.xn--p1ai/pict/file/68056178450.pdfIn PDF document text
    • http://chukguwang.com/files/fckeditor/file/29564724386.pdfIn PDF document text
    • https://wspaperbag.com/userfiles/file/rojomiku.pdfIn PDF document text
    • https://www.hippocratio.gr/ckfinder/userfiles/files/gagofekumumeguveberuv.pdfIn PDF document text
    • http://www.jobibon.com/admin/userfiles/file/84984521367.pdfIn PDF document text
    • http://bakersfield.thepokeluau.com/uploads/files/76415679906.pdfIn PDF document text
    • http://qhchemicalsfeed.com/upload/files/7965410581.pdfIn PDF document text
    • http://sky1981.com/asset/uploads/files/wavigez.pdfIn PDF document text
    • http://stowarzyszeniemalyksiaze.eu/img/upload/files/47741301950.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=pokemon+the+last+fire+red+rom+hackPDF 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_off0000c1fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1FB 10836 bytes
SHA-256: d76001034d47617b5351d12e4c36e8664f0f630881e735479e55fc1ff1312238
font_01_sfnt_off0000dac4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAC4 18264 bytes
SHA-256: 5d3aa13c63deadc7237a2385d7107988b7404b038a9454eec5d06325bf8f5817
font_02_sfnt_off00010a4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A4D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1