Malicious PDF — malware analysis report

Static analysis result for SHA-256 266f8eea3860e9c2…

MALICIOUS

PDF

77.3 KB Created: 2021-11-11 18:58:36 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 844f9dfc1b8ed5d64e0b2cd8cf46eff5 SHA-1: e4c02b2da33e1e6f22642b244b9ee18127fd7cb8 SHA-256: 266f8eea3860e9c236469fbc374084a898d71c8b114d7a07261a578635cb570b
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was identified as malicious by ClamAV and an ML classifier, with critical heuristic firings indicating it is a phishing trojan. Embedded JavaScript is present, which is likely used to redirect the user to malicious URLs. Several URLs were extracted, some pointing to compromised CMS uploads and link farms, suggesting a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

Heuristics 7

  • 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.
  • 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://slxiang.com/v15/Upload/file/202110201035365092.pdf In PDF document text
    • https://lasanisports.com/files/3570949614.pdfIn PDF document text
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615595c9884c1---wuxuzesopadug.pdfIn PDF document text
    • https://optimumquestsolutions.com/ckfinder/userfiles/files/13658332561.pdfIn PDF document text
    • https://adikketiga.com/contents/files/bufutegukewufe.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/4c35mk778f40i8dmtv3nknh6a7/xobewupix.pdfIn PDF document text
    • http://m-styleauto.com/js/upload/files/suxomajapako.pdfIn PDF document text
    • http://www.barbazan-debat.fr/ckfinder/userfiles/files/43345509715.pdfIn PDF document text
    • https://nocnepal.org.np/ckfinder/userfiles/files/36626237336.pdfIn PDF document text
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/9b28a14d6135473eb5e22387d14b4b76/kukowufanupujijosejopexi.pdfIn PDF document text
    • http://alarcon-v.com/editor_upload_image/file/99864731262.pdfIn PDF document text
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/1613044780d31c---17565352618.pdfIn PDF document text
    • https://ewt.cz/res/file/gavom.pdfIn PDF document text
    • https://jesssmithtri.com/jesssmith/ckfinder/userfiles/files/doposotabenepujubero.pdfIn PDF document text
    • https://ibshospitals.com/userfiles/file/11132743930.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/peebfn881mffjo2k907sirumbd/91751366612.pdfIn PDF document text
    • https://likeevent.it/writable/public/userfiles/file/29741921774.pdfIn PDF document text
    • https://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/54b86e6aa1bb532b2fe4174e77edc041/1531053768.pdfIn PDF document text
    • http://st-johnson.com/Uploadfiles/files/devadefuka.pdfIn PDF document text
    • http://hstairan.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/73300712429.pdfIn PDF document text
    • https://pmsp-me.com/userfiles/files/53487329794.pdfIn PDF document text
    • http://asiadomainstore.com/userfiles/file/rujunigeri.pdfIn PDF document text
    • http://vuoncotichdep.com/upload/files/buvujaretadonesetifuke.pdfIn PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/18905b4f6bfc4b0c483cb9b6cc9e3e7d/57249169609.pdfIn PDF document text
    • http://vatlieubaooncachnhiet.com/userfiles/file/98288274874.pdfIn PDF document text
    • http://ucinnovation.ru/admin/ckfinder/userfiles/files/97527212908.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Gsjc/~3/6Zflnl449io/uplcv?utm_term=how+to+recover+unsaved+slides+in+powerpointPDF 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_off0000c694.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC694 18484 bytes
SHA-256: 4138fd97109110d6e2d89240ecc393f3f291110e52dd07ebc2d2ef47a0bfff9f
font_01_sfnt_off0000f6e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6E7 10752 bytes
SHA-256: 4eefaa091319b85ea903542bfbc67365ab693bc2f8998370e824c660391af4ea
font_02_sfnt_off00010fc7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FC7 16540 bytes
SHA-256: 45015263e28dbf00792e0fa83ae0fb9123af5110209f191c00797c49350166ef