Malicious PDF — malware analysis report

Static analysis result for SHA-256 431ff42ec9729e0a…

MALICIOUS

PDF

83.0 KB Created: 2021-09-12 09:16:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 2312e35fa197250bf1227e3aed6c8f9f SHA-1: 4c9f54bbbd16ef93c9e31c45f14a53aa7ba17d06 SHA-256: 431ff42ec9729e0ad568f1c4b9f7c3a6c489846eebeae9f3773a82516c04b1b9
194 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged by multiple heuristics as malicious, including ML classification and ClamAV detection. The critical heuristic 'SE_SECRET_RECOVERY_LURE' indicates the document's intent to trick users into revealing sensitive recovery information. Embedded JavaScript was also detected, suggesting potential for further malicious actions like credential harvesting or payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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
  • Recovery secret / private key request critical SE_SECRET_RECOVERY_LURE
    Document requests recovery phrases, private keys, backup codes, or saved passwords. Requests for these secrets in a document are high-risk.
  • 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://dazhonghua1688.com/ckfinder/userfiles/files/99404540589.pdf In PDF document text
    • http://szwygs.com/upload/25595558440.pdfIn PDF document text
    • http://optykglowacki.pl/obrazki/files/mukanevogapukotinejapuwe.pdfIn PDF document text
    • http://jinistudy.com/_UploadFile/Images/file/xosadorekupifuravajuromo.pdfIn PDF document text
    • https://brianhigbielaw.com/UserFiles/file/43343182037.pdfIn PDF document text
    • http://asacnfservices.com/ckfinder/userfiles/files/gukobevojalirojeverak.pdfIn PDF document text
    • https://rent-1.es/ckfinder/userfiles/files/73684548018.pdfIn PDF document text
    • http://k-ookuma.com/js/upload/files/41033658699.pdfIn PDF document text
    • http://incomingmakedonia.com/files/files/daziwinuxebalidov.pdfIn PDF document text
    • http://kelkenaghshband.com/app/webroot/img/files/vabixogowokexowo.pdfIn PDF document text
    • https://melnikhouse.com/userfiles/file/4197591184.pdfIn PDF document text
    • http://asupuro.com/user_data/image/file/54044196333.pdfIn PDF document text
    • https://alzubidi.com/userfiles/files/41564359176.pdfIn PDF document text
    • https://santa.sg/images/users/00000000/files/sizipopopeg.pdfIn PDF document text
    • https://goodluckfishing.com/ckfinder/userfiles/files/74910162661.pdfIn PDF document text
    • http://umffz21.ru/admin/ckfinder/userfiles/files/jodofikeralatejuto.pdfIn PDF document text
    • http://bjxbw.cn/userfiles/file/34165947859.pdfIn PDF document text
    • http://apexnepaltravel.com/userfiles/file/14286460990.pdfIn PDF document text
    • http://golden-candies.ru/webroot/files/files/sikesi.pdfIn PDF document text
    • https://theshamrockpublecco.it/file/jojuritininesotusosekub.pdfIn PDF document text
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135e593d26c4---vigofafefalokugipubav.pdfIn PDF document text
    • http://uni-soar.com/userfiles/file/22203827928.pdfIn PDF document text
    • http://nonstopsushi.com/uploads/files/20811906085.pdfIn PDF document text
    • http://anhuishangbiao.com/upload_fck/file/2021-9-7/20210907160304137297.pdfIn PDF document text
    • http://presssimayeshahr.ir/pic/file/pexelupixiziropixuv.pdfIn PDF document text
    • https://maychieuvinh.vn/upload/files/silonisibazarafuxuniji.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=best+go+launcher+themes+free+downloadPDF 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_off0000dee8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEE8 11068 bytes
SHA-256: d3256194960c0ce71eb948c5fe2fca53da8add5b7f142babaee2dc5cb99f804d
font_01_sfnt_off0000f873.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF873 17752 bytes
SHA-256: c13dfd128dfec412c18802b6cc007d012263d708b534d94f6e37d7d8749f11d4
font_02_sfnt_off0001268f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1268F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1