Malicious PDF — malware analysis report

Static analysis result for SHA-256 5d91af946dcc8550…

MALICIOUS

PDF

86.6 KB Created: 2021-09-17 15:16:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: d857c67eca77d502bca596f577a6cf2b SHA-1: d663dfc8c53e19c21697623da95ba722f8f666e4 SHA-256: 5d91af946dcc85501a85d6a21d5d99fcff0e230d2c8fd8ba73fb2208c4da331e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded URLs, many of which point to disposable domains and are likely used for phishing or to host malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded links suggest it's designed to redirect users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 5

  • 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.
  • 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://csc0731.com/userfiles/file/20210909114531_i9fbkn.pdf In PDF document text
    • http://sdhmladavozice.cz/userfiles/file/99821951131.pdfIn PDF document text
    • https://photopoligrafic.ru/ckfinder/userfiles/files/kapagima.pdfIn PDF document text
    • https://tpk-m.ru/files/file/zakuw.pdfIn PDF document text
    • http://www.laterveer-biesenbeek.nl/ckfinder/userfiles/files/jikoboj.pdfIn PDF document text
    • https://073741256.com/uploads/files/202109151623147189.pdfIn PDF document text
    • http://buffagiuseppeinfissi.com/userfiles/files/36282744050.pdfIn PDF document text
    • http://omni-links.com/images/blog/file/gavevajutelolivogo.pdfIn PDF document text
    • http://vandientuchinhhang.com/upload/files/89282114709.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16141406a7e500---42294886119.pdfIn PDF document text
    • http://dxczx.com/ckfinder/userfiles/files/20210910_034224.pdfIn PDF document text
    • http://ilkconstruction.com/Images/Media/files/nexexonanijagedira.pdfIn PDF document text
    • https://g-mtcc.com/motakamel/Ups/files/kimenokinekebanuredegi.pdfIn PDF document text
    • https://chsins.tw/uploads/files/202109141748444533.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/55n8jeupg849e32mjh63sjkh9h/41809746914.pdfIn PDF document text
    • http://veterinariacomportamentale.it/userfiles/files/vizuba.pdfIn PDF document text
    • https://gruntbudowa.pl/files/file/zukuki.pdfIn PDF document text
    • http://energosol.pl/images_cms/file/dogixigabejibilowanulojo.pdfIn PDF document text
    • http://mariamozharova.ru/uploads/files/jijabutapelogubi.pdfIn PDF document text
    • http://mundialimportweb.com/userfiles/file/jojamejaweza.pdfIn PDF document text
    • https://pediatricpotentialsnj.com/PP/PPpng/files/nanemimarogumipevok.pdfIn PDF document text
    • http://xn--80aikni6a0b.xn--p1ai/images/file/41176391769.pdfIn PDF document text
    • http://alfatreyd-mebel.ru/archive/images/file/24693652262.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=membuat+kalkulator+dengan+android+studioPDF link annotation
    • http://s292376414.onlinehome.fr/datas/imgmail/file/53421257402.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_off0000f035.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF035 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001084c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1084C 10916 bytes
SHA-256: 0c48f10757b3ca4cd266de7e8eba4b62a9d40a59296ddabc5f1bc7dc9e11d3a7
font_02_sfnt_off00012152.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12152 16764 bytes
SHA-256: a14c9e017270fb22c5bf5464c8871424db5f3c04601edd5d97e0bf846b0b4cdb