Malicious PDF — malware analysis report

Static analysis result for SHA-256 90d17f0aa2ec8a31…

MALICIOUS

PDF

70.3 KB Created: 2021-10-01 08:15:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: fedf6f5c555cfefd7f1e28f8eceac5f3 SHA-1: bf7118caeb8f592c6779373e3085b50e4f46cbe0 SHA-256: 90d17f0aa2ec8a31b14d8ba1c6db13c924b8a7c1b4cfbae9cdd204541273352b
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URIs, many pointing to disposable hosting, suggesting a link farm or phishing lure. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating the PDF is designed to redirect users to multiple external sites. No scripts were extracted, but the overall structure and heuristics point to a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • 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.
  • 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://crysiq.ru/uplcv?utm_term=mrs+dalloway+themes+pdf PDF link annotation
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161495c8c81a8b---zitogorowunikid.pdfIn PDF document text
    • https://fortlauderdale-carservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614714e608848---96502617510.pdfIn PDF document text
    • https://www.hkfew.org.hk/ckfinder/userfiles/files/19755185344.pdfIn PDF document text
    • https://underworldgear.com/upload/users/files/53516636979.pdfIn PDF document text
    • https://texigo.tw/upfile/files/2021/09/05/dilamijiwumifexuruso.pdfIn PDF document text
    • http://muasamhangmy.com/ckfinder/userfiles/files/45343033539.pdfIn PDF document text
    • http://wccflooring.com/userfiles/files/muxumur.pdfIn PDF document text
    • http://changjiujz.com/uploads/files/202109280711437110.pdfIn PDF document text
    • http://itineraire-consulting.com/ckfinder/userfiles/files/89084636395.pdfIn PDF document text
    • http://capriololaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/36186536475.pdfIn PDF document text
    • http://shipagents.nl/uploadfiles/file/3872279839.pdfIn PDF document text
    • https://eric-parnes.shortex.com/ckfinder/userfiles/files/vudapi.pdfIn PDF document text
    • https://kabelkyaobuv.sk/editor_uploads/files/94182932048.pdfIn PDF document text
    • https://birotex.rs/images/files/buwijugisebelogigopisanol.pdfIn PDF document text
    • http://aedjtjdshbf.pretty-match.com/upload/files/19378942396.pdfIn PDF document text
    • https://www.thic.net/plugin/ce1/ckfinder/userfiles/files/97800850793.pdfIn PDF document text
    • http://linkingpeople.info/userfiles/file/peregukasimosoxetipeb.pdfIn PDF document text
    • http://snnet.kr/board_pds/fckeditor/2021/09/file/sirujalododegadamolav.pdfIn PDF document text
    • https://gulf-rope.com/images/bulk_images/files/lirum.pdfIn PDF document text
    • https://clinicaabrahaoosta.com.br/ckfinder/userfiles/files/65606310751.pdfIn PDF document text
    • http://klpa.net/userData/board/file/losiz.pdfIn PDF document text
    • http://specialcats.nl/media/files/94585448814.pdfIn PDF document text
    • https://funbugs.ie/userfiles/file/vevafazikiguwubogubad.pdfIn PDF document text
    • https://oxi-dental.ro/imagini_ws/sozatesira.pdfIn PDF document text
    • http://giustizianuova.it/userfiles/file/nutolupufivinuvewiside.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_off0000b3e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3E7 10760 bytes
SHA-256: 3098086d32a00590c0384b1bbb23299ebc024be45666323c84850f67fbbb2b65
font_01_sfnt_off0000ccc8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCCC8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e4da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4DA 15384 bytes
SHA-256: 52361a295539dbc3b239239b1aab84ed9428e1ef7094b6c3725fd59a3d881b0c