Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8a314042b28bee6…

MALICIOUS

PDF

70.8 KB Created: 2021-09-25 10:15:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: c7e64d254caf1bacb6e10eb6484deffe SHA-1: 92f4787ad81c5282686bedc6f16a991f7a207f37 SHA-256: a8a314042b28bee6733e9bfafbfff92e8719bab7028c5e3009be5b62b6daa652
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 likely used to facilitate redirection to these malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9909

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://synerhu.ru/uplcv?utm_term=calisthenics+workout+plan+intermediate+pdf PDF link annotation
    • https://stehovani-ostrava.cz/static_pages_files/file/48429587291.pdfIn PDF document text
    • http://perechen-izdaniy.ru/js/ckfinder/userfiles/files/86623200790.pdfIn PDF document text
    • http://donauwell.at/userfiles/file/26851396433.pdfIn PDF document text
    • https://anaksemut.com/contents/files/xijenobiverigu.pdfIn PDF document text
    • https://lp-tracking.com/userfiles/file/18343475877.pdfIn PDF document text
    • http://gazosilikatnn.ru/uploads/files/98132481481.pdfIn PDF document text
    • http://emilymillerlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/sepewodomanaledu.pdfIn PDF document text
    • http://jyotiacademicpress.org/uploads/file/62241879395.pdfIn PDF document text
    • https://thenovgorodspaceship.andreirozen.com/images/files/nikekejonutidutotezo.pdfIn PDF document text
    • http://herium.net/FileData/ckfinder/files/20210925_414DFC606F660DA2.pdfIn PDF document text
    • http://energyexcess.com/userfiles/file/68444368091.pdfIn PDF document text
    • http://transbur.ru/admin/ckfinder/userfiles/files/najilakikudiwe.pdfIn PDF document text
    • https://parquesanalbertohurtado.cl/ckfinder/userfiles/files/salerogudenob.pdfIn PDF document text
    • http://qianxish.com/ckfind_image/files/92365484846.pdfIn PDF document text
    • https://laughteronlineuniversity.com/images/upload/files/73491391399.pdfIn PDF document text
    • http://indianmailbox.com/assets/images/userfiles/files/lumiresaxafolaturerub.pdfIn PDF document text
    • https://haruhonpo.com/upload/haruhonpo/files/58538865538.pdfIn PDF document text
    • https://hchoanglong.vn/userfiles/file/92419056399.pdfIn PDF document text
    • http://vantaidongsaigon.com/uploads/files/51575357786.pdfIn PDF document text
    • http://improntediteatro.it/userfiles/files/82419726303.pdfIn PDF document text
    • https://rezilta.com/psum/admin/userfiles/file/60781114337.pdfIn PDF document text
    • https://sonerofset.com/userfiles/file/palajuzidivegijojekozaj.pdfIn PDF document text
    • http://roycraft.ca/userfiles/file/17867435487.pdfIn PDF document text
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/16140e5f0eb518---nepekeveg.pdfIn PDF document text
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/8466d5ef0661416da67157b3529a884d/vojokinimigubaka.pdfIn PDF document text
    • http://systempro.kr/userData/board/file/lerenoxiridimatepitovag.pdfIn PDF document text
    • https://tvmreza.tv/ckfinder/userfiles/files/lazekumimofinutone.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_off0000b5af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB5AF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cdc1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDC1 14688 bytes
SHA-256: f41a15ba8644b714d58350aa8a0d10ae8545769ce97558afac81af7454975d4e
font_02_sfnt_off0000f26f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF26F 11192 bytes
SHA-256: 793f4c0b5d48f4f2cffda617bcae6f0c9fd60f312301936b51dd2ae037c21165