Malicious PDF — malware analysis report

Static analysis result for SHA-256 2c9b71c1934f3a9e…

MALICIOUS

PDF

70.0 KB Created: 2021-09-20 04:04:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 2435f1658c566249ef52878027b0cb72 SHA-1: da299173d9bc3793feb564687d870483027b592c SHA-256: 2c9b71c1934f3a9e29a6ec18633902f67011ea6479d7cb92c504d89b21d12945
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which are part of a link farm hosted on potentially compromised websites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to trick users into downloading malware disguised as legitimate files. The presence of JavaScript suggests it may be used to facilitate the download or execution of further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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 https://coretry.ru/uplcv?utm_term=android+game+obb+file+download PDF link annotation
    • http://shlawllc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/55557934853.pdfIn PDF document text
    • http://kozelskadm.ru/files/uploads/files/nubaritujorilurego.pdfIn PDF document text
    • http://www.mediacomriccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/161420c1ada10f---vixezorij.pdfIn PDF document text
    • https://minlinart.com/archive/upload/files/13993407511.pdfIn PDF document text
    • http://park-seversk.ru/other/js/ckfinder/userfiles/files/78843398348.pdfIn PDF document text
    • http://easytravel63.ru/ckfinder/userfiles/files/60725398765.pdfIn PDF document text
    • http://crm333.com/documentos/file/wokufube.pdfIn PDF document text
    • http://bluebiz.kr/userData/board/file/9754872153.pdfIn PDF document text
    • https://bunyaminerdemir.com/resimler/files/30402408657.pdfIn PDF document text
    • http://lejuriste.ru/files/file/42276829266.pdfIn PDF document text
    • http://vijyaiprismcrm.com/userfiles/files/60339770404.pdfIn PDF document text
    • https://mr-alian.com/upload/ckfinder/files/telob.pdfIn PDF document text
    • http://hnkingdee.cn/Files/file/20219820439.pdfIn PDF document text
    • https://imagebeaute.fr/userfiles/file/buzamogasawo.pdfIn PDF document text
    • http://hopkim.vn/upload/files/loniwogez.pdfIn PDF document text
    • http://architettoletiziamasciotta.eu/userfiles/files/65150045190.pdfIn PDF document text
    • https://rmdschoolandcollege.com/wp-content/plugins/super-forms/uploads/php/files/8d62d2074b460f1eaab192cee692cf19/nejitovoxa.pdfIn PDF document text
    • http://wieswioska.pl/userfiles/file/71413875445.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614172a9dce5f---rejebob.pdfIn PDF document text
    • https://madame-tina.com/ckfinder/userfiles/files/vosoguxelatatipazajepip.pdfIn PDF document text
    • http://paletydozahrady.cz/ckfinder/userfiles/files/13321049514.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_off0000b3e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3E5 10640 bytes
SHA-256: 6c07476b46994dddeb0f2e82295e89d5670062d981441d6bc12a86a11017cf1b
font_01_sfnt_off0000cc0c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC0C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e41e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE41E 15128 bytes
SHA-256: 061c61316929a8dc99edd2805c206c80a8c7e53bffd537f14a0d8734f88f448a