Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf86db7204a6e60c…

MALICIOUS

PDF

79.7 KB Created: 2021-09-20 13:36:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1311cbb1e0434ebdbda4b0de674b5034 SHA-1: 273f9c488f556778bd0f04c18b3f0a95b2705fb1 SHA-256: bf86db7204a6e60c614a6dbe3aa5979f6b50a89e2a92370e46b901f07239defc
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 hosted on disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded JavaScript is a common technique for exploiting PDF vulnerabilities or redirecting users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://cructi.ru/uplcv?utm_term=fairy+tail+live+wallpaper+for+android
    • https://vico-inmobiliaria.com/ckfinder/userfiles/files/34039963423.pdf
    • https://www.delaneyllc.com/ckfinder/userfiles/files/86501004569.pdf
    • http://epoch-making.jp/js/upload/files/pewiwowatujutafedo.pdf
    • https://happyfun.tw/uploads/files/202109090631583880.pdf
    • http://hndgyl.com/v15/Upload/file/202195112216079.pdf
    • http://orderleesushi.com/uploads/files/tusogotoneteboko.pdf
    • http://mkconline.com/landmark/ckfinder/userfiles/files/zokizasolugifividerizene.pdf
    • https://silverbirdmarketing.com/pages/images/file/7689759285.pdf
    • http://prepearl.com/uploadsfile/42522329482.pdf
    • https://www.karelo.com/uploads/File/bufizekilexewu.pdf
    • http://naitikfashions.com/ckfinder/userfiles/files/tivuluxunopet.pdf
    • http://fullerton.kopanramen.com/uploads/files/96227605309.pdf
    • https://cashcruis.ru/wp-content/plugins/super-forms/uploads/php/files/2e57bc4b0dfbec4be932e15cd18e63cb/75571508256.pdf
    • https://backcountryplayground.com/wp-content/plugins/super-forms/uploads/php/files/0d7213f69d017bba2c5cda2a790a885b/bopuwibozuvimevubi.pdf
    • http://kartelabasligi.com/images_upload/files/15453105090.pdf
    • https://sakura-bashi.com/uploads/files/202109140313128139.pdf
    • http://mxag.com/upload/browse/file/36028717099.pdf
    • https://clinicaabrahaoosta.com.br/ckfinder/userfiles/files/5076042108.pdf
    • http://lubrifianti-auto.ro/files/file/galaful.pdf
    • http://kortennis.co.kr/B/ck/ckfinder/userfiles/files/15354402322.pdf
    • https://kmkmekanik.com/upload/ckfinder/files/71905506683.pdf
    • https://calson.garment-pro.com/ckfinder/userfiles/files/38901735627.pdf
    • http://stjconsulting.it/userfiles/files/9263566061.pdf
    • https://alharithiforcameras.com/ckfinder/userfiles/files/34343435681.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d5c8.bin
45052c88115d1783d56bf4e8cb35244a9b1e646ed599954411848c89eb9b0265
pdf-font-stream PDF embedded font (sfnt) at offset 0xD5C8 16504 bytes
font_01_sfnt_off000100a7.bin
0371b9ff29babaeb593a218b4f96cf6ff1ba0737c7910dbc586dd4494074a709
pdf-font-stream PDF embedded font (sfnt) at offset 0x100A7 10564 bytes
font_02_sfnt_off000118e4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x118E4 16792 bytes