Malicious PDF — malware analysis report

Static analysis result for SHA-256 53bd507931cf8ac6…

MALICIOUS

PDF

80.1 KB Created: 2021-09-10 16:48:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-27
MD5: 7b3a708ebf79b7902a9fa7e14e2decb7 SHA-1: d5912f2003e52bc5302dd430b7d386c634eaf097 SHA-256: 53bd507931cf8ac613eaf5e4b936389696191829336cadaab331e2c73bec8829
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code within documents. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript likely facilitates the redirection to external URLs, as evidenced by the numerous URLs found, including one flagged as a link farm, suggesting a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://acecaalcoy.com/userfiles/file/maragovojumos.pdf In PDF document text
    • http://gok-maciejowice.pl/js/ckfinder/userfiles/files/75220267837.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/16137e17199890---pobokujuga.pdfIn PDF document text
    • https://ausztriasi.spawellness.hu/upload/hirlevel/files/ravis.pdfIn PDF document text
    • https://apatity.verlauf-ekb.ru/admin/ckfinder/userfiles/files/viravurawovipebopezo.pdfIn PDF document text
    • http://www.park-seversk.ru/other/js/ckfinder/userfiles/files/gibogasukufi.pdfIn PDF document text
    • http://birizgardenhotel.com/userfiles/file/lusizewisav.pdfIn PDF document text
    • https://amt-alarmy.pl/userfiles/file/69603934120.pdfIn PDF document text
    • http://www.village-gaulois.org/gestion/ckfinder/userfiles/files/wanuvefirulilasixuper.pdfIn PDF document text
    • http://gediklimakinahidrolik.com/resimler/files/gopomawimamakaxofi.pdfIn PDF document text
    • https://channeloflove.com/ckfinder/userfiles/files/67788778134.pdfIn PDF document text
    • http://notar-frings.de/userfiles/file/geponukefof.pdfIn PDF document text
    • http://trungnguyenjsc.vn/uploads/image/files/21569072832.pdfIn PDF document text
    • http://thoitrangvabaoho.com/Images_upload/files/80147721348.pdfIn PDF document text
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613188175526b---71546650607.pdfIn PDF document text
    • https://spvi.cn/filespath/files/20210906070642.pdfIn PDF document text
    • http://hoya-system.com/uploads/files/202109100301376240.pdfIn PDF document text
    • http://dspec-car.com/js/upload/files/73837636423.pdfIn PDF document text
    • http://bhhangkhong.com/upload/images/files/giduwotedu.pdfIn PDF document text
    • http://suriyedostlukdernegi.org/image/files/ziduromipanivefeduzufuwev.pdfIn PDF document text
    • http://ambvetbrashersclavoghisu.eu/userfiles/files/45095158626.pdfIn PDF document text
    • https://anna-bel.com/app/webroot/files/userfiles/files/wivak.pdfIn PDF document text
    • https://parkettworld.com/upload/files/47718677459.pdfIn PDF document text
    • https://needlugs.com/userfiles/files/ritirogikolobijagetifuge.pdfIn PDF document text
    • http://galerie45.com/userfiles/file/74664869035.pdfIn PDF document text
    • https://eminentland.com/admin/userfiles/files/98727813567.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=ethical+principle+of+veracityPDF 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_off0000d75c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD75C 16964 bytes
SHA-256: f144eea5d2d22e5635bd9714d126ae618a56823ea882ba0cfe64ca8807245c16
font_01_sfnt_off000102a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102A3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011aba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11ABA 10572 bytes
SHA-256: 5a8f6a9108cba62d641c2416c3a4dcc3ef13dd235eda6860e476833fd043b8c5