Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4ddd91460dc3e87…

MALICIOUS

PDF

80.8 KB Created: 2021-09-23 15:45:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 674535cd87841e728daf9ff029aa0b52 SHA-1: eef70782588c61d3150db86e980c253ae97066be SHA-256: d4ddd91460dc3e87138b7f4de4ca3dd2d0da1b28617002dea449943ed260ba1d
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The presence of embedded JavaScript and a large number of external URIs, many pointing to disposable domains, suggests an attempt to distribute malicious content or conduct phishing. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports the idea of a link farm designed to obscure the true malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 http://kcntanduc.vn/img_duhoc/files/momirebegulisuxenavabere.pdf In PDF document text
    • http://moutierrozeille.fr/userfiles/file/fanavifi.pdfIn PDF document text
    • https://www.jnvhardoi.org/ckfinder/userfiles/files/kovizodizomuran.pdfIn PDF document text
    • http://huspanda.com/data/ckfinder/files/wewipibimi.pdfIn PDF document text
    • https://stgeorgedentalcare.in/ckfinder/userfiles/files/93172733025.pdfIn PDF document text
    • http://kursverwaltung.fit-n-essen.ch/ckfinder/userfiles/files/20963048009.pdfIn PDF document text
    • http://sadiqandsons.com/userfiles/files/16536413208.pdfIn PDF document text
    • http://szsahsh.com/uploads/files/zisidetevi.pdfIn PDF document text
    • http://speckletrack.com/update/editor/file/teradubigiz.pdfIn PDF document text
    • http://adec-interiors.net/Uploads/file/ramagitalilobivujuwu.pdfIn PDF document text
    • https://die-elke.de/cms/elke_page_files/file/58697144832.pdfIn PDF document text
    • http://dichvubaove.online/upload/files/napobasuwomup.pdfIn PDF document text
    • http://volareinmongolfiera.it/userfiles/files/naxitokogotemajuseropoz.pdfIn PDF document text
    • http://legalinet.eu/userfiles/files/vojuwebowalazaxel.pdfIn PDF document text
    • http://knshzj.com/CKEdit/upload/files/75222255419.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1612ef26b11609---komebetedomaxurilodegu.pdfIn PDF document text
    • http://newgrids.com/userfiles/file/11803788719.pdfIn PDF document text
    • https://tezerwatch.com/file/upload/files/09-12-20-48-56-11.pdfIn PDF document text
    • http://elijasprojekts.lv/files/file/jimekike.pdfIn PDF document text
    • http://carneiro-sa.pnh.pt/js/ckfinder/userfiles/files/33039799114.pdfIn PDF document text
    • http://architettogherardi.eu/userfiles/files/48751055196.pdfIn PDF document text
    • http://crystaltrade.hu/data/file/22314456935.pdfIn PDF document text
    • http://interstyle.org/content/xuploadimages/file/limeni.pdfIn PDF document text
    • https://borderpak.com/wp-content/plugins/super-forms/uploads/php/files/1f35aa72b0f253fa132034819266d949/dozog.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=how+to+fix+internal+storage+running+outPDF 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_off0000d733.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD733 10668 bytes
SHA-256: b0ba6f3410c02c709f4ba4c9ff81f180574aca0da0b8a3a64ffea62553958aa3
font_01_sfnt_off0000efd0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFD0 17724 bytes
SHA-256: aa31cf399b91cfc296fd3375085efe0443b1a180eb236a5bbdb717ffcdcf9b1e
font_02_sfnt_off00011d6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D6B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1