Malicious PDF — malware analysis report

Static analysis result for SHA-256 ebc2aee0d429b579…

MALICIOUS

PDF

68.1 KB Created: 2021-06-25 04:05:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: 3fd5552e9a7d642cccdb97d28fa0e2b6 SHA-1: 37d392b91e92110d80a11db1a70b16f34d908374 SHA-256: ebc2aee0d429b579e1613b94e8f6f2f5262a14a52ee3e93fc98f8ab313f273ff
164 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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 https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160852546df5a0---60455627099.pdf In PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/jn0fh74k970t5vgh8b8277s4id/88638534588.pdfIn PDF document text
    • http://hyperasp.net/userfiles/file/wuvivofu.pdfIn PDF document text
    • http://linkingpeople.info/userfiles/file/89761227812.pdfIn PDF document text
    • http://marinapogon.pl/upload/file/17838595877.pdfIn PDF document text
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b292c006a4a---38530266845.pdfIn PDF document text
    • http://innospectrum.eu/hirlevel/file/70488700562.pdfIn PDF document text
    • http://secretinvitation.net/images/files/30599474486.pdfIn PDF document text
    • http://rentbucharest.net/images/userfiles/71483566034.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160cbb2c3bef8c---31556211955.pdfIn PDF document text
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c2a496edaa1---dubodemurisufun.pdfIn PDF document text
    • https://kantankacreative.com/wp-content/plugins/super-forms/uploads/php/files/c0c5afaec6503e43061785ef39e7884a/27172301326.pdfIn PDF document text
    • https://stopserv.ru/files/file/biwonexobixoz.pdfIn PDF document text
    • http://sklepjola.pl/userfiles/file/1417871723.pdfIn PDF document text
    • http://grupomarsamo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160767977665e4---4531550384.pdfIn PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d50e1728df3---80282379080.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=gst+letter+of+authorisation+formatPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ce22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE22 5036 bytes
SHA-256: f4b55500e06e45220c797e5becfe3dac71bd56421e04197ed71a956d6394168d
font_01_sfnt_off0000df16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF16 10636 bytes
SHA-256: 750e203ac72392d24c18f916f83b58541919af1c5e73b388d99c9f457f6cfa4e