Malicious PDF — malware analysis report

Static analysis result for SHA-256 bc356c25390aba48…

MALICIOUS

PDF

90.4 KB Created: 2021-09-22 10:54:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: f9c88f261862c70bd1dfc1a31710187e SHA-1: 83078d63e402f197eaf9bd2f5a8eb10104adfe0f SHA-256: bc356c25390aba484c6bcebfa2eeacd436ddb14745631c2b36301df8282098f0
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for executing malicious code. The PDF also contains numerous external URIs, many of which point to disposable hosting, suggesting a link farm or phishing operation. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to malicious sites or download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9930

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://oniceh.ru/uplcv?utm_term=aplicaci%C3%B3n+para+ver+pel%C3%ADculas+gratis+android PDF link annotation
    • https://spencershaulageltd.co.uk/wp-content/plugins/super-forms/uploads/php/files/0e2d3eb02b60ac105b2ff8c315a4af08/33125781039.pdfIn PDF document text
    • http://peak-experience-japan.fr/images/blog/file/23755918206.pdfIn PDF document text
    • http://alternativefitness.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161409063ac8bc---32279480203.pdfIn PDF document text
    • http://animalscipublisher.com/files/upfiles/file/vunezotozadaxumawepaxadoz.pdfIn PDF document text
    • http://cpbnatation.fr/fckeditor/userfiles/file/fegudepekezubogi.pdfIn PDF document text
    • http://conservativista.com/js/ckfinder/userfiles/files/85306215808.pdfIn PDF document text
    • https://askisan.com/upload/ckfinder/files/83559401078.pdfIn PDF document text
    • http://guides2alpes.org/uploads/file/18087083181.pdfIn PDF document text
    • https://hw-power.com/uploads/ckfiles/files/6146b509c9e78.pdfIn PDF document text
    • http://moje-stranky.eu/userfiles/file/madaguvegexa.pdfIn PDF document text
    • https://tanhaithanhvalves.com/quangcao/admin/file/wafosorikekamerugusironuj.pdfIn PDF document text
    • http://grandwatergatehotel.com/upfile_hotel/files/26013001212.pdfIn PDF document text
    • http://be-now.pl/userfiles/file/99599886561.pdfIn PDF document text
    • http://bigcool.net/webroot/img/files/69288954273.pdfIn PDF document text
    • https://agronlogistics.com/userfiles/files/nasegitabosoxizi.pdfIn PDF document text
    • http://nokianhakkablue.ru/ckfinder/userfiles/files/2764059004.pdfIn PDF document text
    • http://hbaoge.com/upload/files/jurofupadafowow.pdfIn PDF document text
    • http://stilna-ya.com/_userfiles/file/52043997686.pdfIn PDF document text
    • https://kitapkaplama.com/upload/ckfinder/files/861889251.pdfIn PDF document text
    • https://keongracun.org/contents/files/gusew.pdfIn PDF document text
    • http://erainbowrealty.com/userfiles/file/8868146103.pdfIn PDF document text
    • https://kingbakerypans.com/userfiles/file/20348807408.pdfIn PDF document text
    • https://mimpi1pusat.com/contents/files/1638224675.pdfIn PDF document text
    • https://pbchistoryonline.org/uploads/file/bijakumojuduxugixufiduk.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_003_off0000ddf4.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0xDDF4 17732 bytes
SHA-256: 0e19d1821343d93fd1ff15a6e4715aece49b7d88fe51018c80733b074c0e7298
font_01_sfnt_off0000f926.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF926 18204 bytes
SHA-256: b687f4dfc68cf27174de3e63290359ccd99d35f40fb28cde14ea642524d8af1c
font_02_sfnt_off0001272b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1272B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off00013f42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F42 11036 bytes
SHA-256: e44bba03b1c3097e87866467e718cf3511734aad8edcfc77a81034ebcb97323f