Malicious PDF — malware analysis report

Static analysis result for SHA-256 51c48cefb01a26d5…

MALICIOUS

PDF

87.1 KB Created: 2021-07-26 04:13:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 2ccdbeb4b039f8a3baf34bda4ba2b878 SHA-1: a375425b119419d7315c1a1e8faa0b1648c33e33 SHA-256: 51c48cefb01a26d5ff763a94c9938ac7cce7a886d9c1528909d11544d38b5c33
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by ML and ClamAV as malicious, indicating it likely contains an exploit. It features a link farm pointing to multiple PDF files hosted on compromised CMS uploads, suggesting a distribution or SEO poisoning campaign. The presence of external URIs and a high ML score supports the classification as a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://www.protectakoteasia.com/ckfinder/userfiles/files/53209075024.pdf In PDF document text
    • http://maychamsocda.vn/images/userfiles/file/rufemiguvisapuf.pdfIn PDF document text
    • http://champaigncursillo.com/userfiles/file/sewemobetaxupuxoma.pdfIn PDF document text
    • http://ebslang.net/_UploadFile/Images/file/mukoziwagaxediwoneve.pdfIn PDF document text
    • http://shinies.ru/img/lib/file/19562604502.pdfIn PDF document text
    • http://ahkjt.com/upfile/file/14643505910.pdfIn PDF document text
    • https://brs.jo/userfiles/files/81942125648.pdfIn PDF document text
    • https://noithatkuongthinh.com/uploads/files/fetoxuvupifadaz.pdfIn PDF document text
    • http://saopauloairporttransfers.com/ckfinder/userfiles/files/zezetoluloraroxiwuj.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/954e426026ecdf391e5d99a8f1958f40/28217383554.pdfIn PDF document text
    • http://mazdooradda.com/userfiles/file/2777810338.pdfIn PDF document text
    • http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/1607b42af04152---madinovoxanuwejanomosed.pdfIn PDF document text
    • https://jfefood.com/wp-content/plugins/super-forms/uploads/php/files/e3101544c2f37c407fa18b8250c08933/dogatubiloxaduxugabazaja.pdfIn PDF document text
    • http://poltinka.ru/userfiles/file/95055936131.pdfIn PDF document text
    • http://ewinghighclassof1963.com/clients/e/e4/e4cb61fc1babc639533983e887b7272d/File/putotefijutawifo.pdfIn PDF document text
    • http://moda-minulosti.cz/docs/momin/file/mifaxu.pdfIn PDF document text
    • http://vasvaripalmuzeum.hu/upload/file/15552153156.pdfIn PDF document text
    • http://cesiedizioni.com/userfiles/file/52534749904.pdfIn PDF document text
    • http://flightshop.jp/images/blog//file/9819143127.pdfIn PDF document text
    • https://pinotcar.com/wp-content/plugins/super-forms/uploads/php/files/90bd352029eb5e3708e96f8cd339e3f7/50726160966.pdfIn PDF document text
    • http://mai-colle.jp/userfiles/file/lukikum.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/234c91c7c9ab055384395c6396e99918/goxelokepazo.pdfIn PDF document text
    • http://mnwebdesign.dk/userfiles/file/biliwoduvinusasivex.pdfIn PDF document text
    • http://nuestratierrapremios.com/campannas/file/9499986220.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=troy+full+movie+download+in+hindi+720p+filmyzillaPDF 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_off0000f036.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF036 11176 bytes
SHA-256: a8e378fc5e210bf28dcf054a9f82077d6be2473de8c0b007032df5eda2caba24
font_01_sfnt_off00010a40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A40 16712 bytes
SHA-256: 2282e95ecf90705ef91331183c05b67a21def6cb2c64d80a0e2b3bb91915c483
font_02_sfnt_off000135cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135CF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1