Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b711e169593c1df…

MALICIOUS

PDF

87.6 KB Created: 2021-09-09 07:55:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: a29646b4612f6f15f7c7bd0c9921e4ce SHA-1: ba945f9bab3669968cea340017debb66a66f9d9b SHA-256: 5b711e169593c1df45c4cfc1cbfc20aa064aaa5c8a27f373650d6d0a19134bd7
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many pointing to PDF files hosted on various domains, suggesting a link farm or redirection mechanism. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a tactic to obscure the true destination. While no scripts were explicitly extracted, the nature of the embedded URLs and the ML detection suggest it may leverage PDF vulnerabilities or embedded JavaScript to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 http://artgrafika.cz/userfiles/file/fepavafawomi.pdf In PDF document text
    • https://canionglobal.com/FCKeditor/file/xutimorixekirinamozepap.pdfIn PDF document text
    • http://levotst.com/uploads/files/zisamagorabawasukiwoj.pdfIn PDF document text
    • https://www.andyselfstorage.co.uk/wp-content/plugins/super-forms/uploads/php/files/a0iot2ejc0jik4fhtfl40bs5cb/70937484207.pdfIn PDF document text
    • http://cathugo-catamarans.de/res/wysiwyg/file/sezis.pdfIn PDF document text
    • https://medosojewellery.com/userfiles/files/3881047851.pdfIn PDF document text
    • https://orsam.org.tr/paketler/ckfinder/dosyalar/files/15261233273.pdfIn PDF document text
    • http://fosterfreezesantarosa.com/uploads/files/75089535290.pdfIn PDF document text
    • http://dreiseengrundschule.de/files/5211854895.pdfIn PDF document text
    • http://www.sindafaz.com.br/admin/editor/ckfinder/userfiles/files/10494809164.pdfIn PDF document text
    • http://sibzakon.ru/ckfinder/userfiles/files/48786193839.pdfIn PDF document text
    • https://nhabe.com.vn/ckfinder/userfiles/files/pafafowetoz.pdfIn PDF document text
    • http://franceplus.fr/userfiles/file/tibajiger.pdfIn PDF document text
    • https://thegioidongphuc.net/ckfinder/userfiles/files/54403449798.pdfIn PDF document text
    • http://badischer-kunstverein.de/ckfinder/userfiles/files/newajiposelesetenesupiwif.pdfIn PDF document text
    • http://antropolog.ru/userfiles/file/51207341001.pdfIn PDF document text
    • http://lenosada.sk/editor_uploads/files/37405470505.pdfIn PDF document text
    • http://0vote.com/ckfinder/files/noxanedosixevifimarin.pdfIn PDF document text
    • http://potentialdesign.cn/userfiles/file/1630537076.pdfIn PDF document text
    • http://rockhouseschool.com/rockhouse/uploads/files/sipeseta.pdfIn PDF document text
    • https://hanakspotrebice.cz/eshop/ckfinder/userfiles/files/gulaluvelibakowusokum.pdfIn PDF document text
    • https://spbmworld.com/anaeter_capital/siteadmin/userfiles/files/31559295854.pdfIn PDF document text
    • https://harpethvalleypto.org/wp-content/plugins/super-forms/uploads/php/files/02b33a3231973c5a86a2a0e8f4d84f35/57472785028.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=dont+breathe+tamil+moviePDF 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_off0000f0f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0F4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001090b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1090B 10412 bytes
SHA-256: 600e1bc69dbd36a1fca86b5dcb216c776c267a8bb576c351008df95fb374bfac
font_02_sfnt_off00012063.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12063 18572 bytes
SHA-256: ef23703e94e4a7ddbd08c0a958b6fa6c70273fdc09f25335375b64b85b661482