Malicious PDF — malware analysis report

Static analysis result for SHA-256 1001c9efe72db06a…

MALICIOUS

PDF

81.4 KB Created: 2021-09-16 23:45:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 9ed74079109ba983db268a050dea6aa2 SHA-1: 31ff0aa311be55f0dff83c0900518f4d4e7709bd SHA-256: 1001c9efe72db06a64a8282370fdf4168e4c5880377f1623a3482e0447c26744
134 Risk Score

Malware Insights

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

The sample is a PDF file identified as malicious by ClamAV and an ML classifier. It contains an embedded JavaScript stream and multiple external URIs, including one pointing to 'smidgel.ru'. The PDF's structure and the presence of numerous links suggest it is part of a link farm designed to redirect users to potentially malicious websites. The embedded JavaScript likely facilitates the redirection or exploits a vulnerability.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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 https://smidgel.ru/uplcv?utm_term=fs+14+unlimited+hack PDF link annotation
    • https://www.santaterezinha.com.br/js/ckfinder/userfiles/files/rutemuratelazazerumij.pdfIn PDF document text
    • http://fasson.vip/images/editor/files/56062096386.pdfIn PDF document text
    • http://monthclean.com/uploads/files/202108311720143935.pdfIn PDF document text
    • https://china-glass-mosaic.vegner.com/userfiles/files/20210909_064905.pdfIn PDF document text
    • http://www.gamylai.vn/uploads/files/43588200389.pdfIn PDF document text
    • http://uhorder.com/upload/files/13760115923.pdfIn PDF document text
    • http://ensky-chemical.com/upload/files/dujerebegejilu.pdfIn PDF document text
    • https://tsegypt.com/file/66563150182.pdfIn PDF document text
    • https://familienbilstrup.dk/userfiles/file/fozokomezizage.pdfIn PDF document text
    • http://vipnovini.bg/root/f/uploads/files/76967577298.pdfIn PDF document text
    • http://issaproject.com/app/views/panel/ckfinder/userfiles/files/zikodez.pdfIn PDF document text
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ecae61f25d---garipigarimafosed.pdfIn PDF document text
    • https://www.wsbe17hongkong.hk/_bin/ckfinder/userfiles/files/23278033815.pdfIn PDF document text
    • http://kanizsakran.hu/userfiles/file/xezuvirikizujijenabupasaj.pdfIn PDF document text
    • http://brava-ekb.ru/userfiles/file/seserifubawumukufix.pdfIn PDF document text
    • http://guidesdugrandlarge.fr/images/import/file/86661730176.pdfIn PDF document text
    • http://ppogrimall.com/upload/editor_image/file/resefudumevakixefadozapon.pdfIn PDF document text
    • https://worldpigment.com/image/upload/File/dalasabatowasetulok.pdfIn PDF document text
    • http://thedewakohchang.com/image/upload/File/ujajagebojuve.pdfIn PDF document text
    • http://kowalstwwo.pl/public/cms/images/file/mupumakuzo.pdfIn PDF document text
    • http://aow.infogestnet.it/ckfinder/userfiles/files/durezugiwelimefeveperok.pdfIn PDF document text
    • http://ed-web.cz/userfilesfile/wimiwivitibivofopudofe.pdfIn PDF document text
    • http://mascotdd.com/file_media/file_image/file/rugewogobibudububozazaji.pdfIn PDF document text
    • http://cardealer-space.com/js/upload/files/92787488555.pdfIn PDF document text
    • https://siliconautomation.com/userfiles/file/fosomimivof.pdfIn PDF document text
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612fc0d5766e3---74927277163.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_off0000dc63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC63 16564 bytes
SHA-256: 8b26b035c69f84f4aa89fdc977a5ef56c2ec50571033c13f959ca7087aa344c3
font_01_sfnt_off0001074f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1074F 10716 bytes
SHA-256: 161a52bdcc0638bb1b195fde6b63b5ecd4aca93a2aefd1c6e629a3a928e3479e
font_02_sfnt_off00011fc1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FC1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1