Malicious PDF — malware analysis report

Static analysis result for SHA-256 1ceebd58eb897166…

MALICIOUS

PDF

75.7 KB Created: 2021-09-11 04:25:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: ba54169693b7d71da6a66d99be4e8add SHA-1: 4be2e3fd2fd7f4e33d11ce4dd244f9427edfd2a9 SHA-256: 1ceebd58eb897166e72be71197a448acbb21d42cc21f5ebdad5b6497df5fa16d
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to disposable domains, indicating a link farm or phishing lure. The ClamAV detection and ML classifier strongly suggest malicious intent, likely to redirect users to sites hosting malware or phishing content. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document designed to exploit users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://vipnjl.com/userfiles/files/67121399722.pdf In PDF document text
    • http://locthanhroyal.com/upload/files/32800846315.pdfIn PDF document text
    • http://agt.es/files/galeria2/files/24186977299.pdfIn PDF document text
    • http://thuduchouse.vn/pics/file/fasopigudenofixewazafufe.pdfIn PDF document text
    • https://aymexco.eu/ckfinder/userfiles/files/saliro.pdfIn PDF document text
    • https://ferest.ro/imagini_ws/14186764073.pdfIn PDF document text
    • http://clingac.es/d/files/9605190864.pdfIn PDF document text
    • https://xanbiente.de/userfiles/file/lubapobejakovupazupalebun.pdfIn PDF document text
    • http://jj-metals.com/userfiles/file/2021090316170073499.pdfIn PDF document text
    • http://filtrydokoparek.pl/img/all/roxixolitukezekam.pdfIn PDF document text
    • http://megaprestige.ru/uploads/files/45472959242.pdfIn PDF document text
    • https://www.willmarareachamber.com/ckfinder/userfiles/files/83331387176.pdfIn PDF document text
    • http://gibisch.org/files/files/83087535522.pdfIn PDF document text
    • http://ambulatorioveterinariovianello.eu/userfiles/files/tubuwug.pdfIn PDF document text
    • http://metamorfozyayincilik.com/userfiles/file/merajiregobibuzumapir.pdfIn PDF document text
    • http://fernandopelosini.it/userfiles/files/zapitakavoderukafigumus.pdfIn PDF document text
    • https://nsck-cykelmotion.dk/userfiles/file/rilapojojolupoxuwinub.pdfIn PDF document text
    • https://cailux.lu/userfiles/files/vebozevifijoboxog.pdfIn PDF document text
    • http://www.me.ntou.edu.tw/ckfinder/userfiles/files/20210905_074847.pdfIn PDF document text
    • https://ebooksweb.net/files/file/94286927113.pdfIn PDF document text
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/161324f14af36f---78544067566.pdfIn PDF document text
    • https://conexusinternational.com/ckfinder/userfiles/file/88121703746.pdfIn PDF document text
    • http://usaoxin.com/userfiles/2021-9/file/wasuzega.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=how+to+delete+all+your+emails+at+once+on+androidPDF 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_off0000c3fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3FD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dc14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC14 10824 bytes
SHA-256: 1aabdc051c251858b0d90060b5b28bc369c2ef88cc6597194623af759bde35be
font_02_sfnt_off0000f510.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF510 17108 bytes
SHA-256: d1c455d9afdbab0406b36c0613fdf477e5603df8e8a0c06bb57d7be1a69d7ca7