Malicious PDF — malware analysis report

Static analysis result for SHA-256 bc58bb402b252ade…

MALICIOUS

PDF

78.6 KB Created: 2021-07-22 10:42:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 94f223f619a17690279f1c7d0335d29f SHA-1: 28833a461791d2dddabeb8af0222bdb1615ccd6a SHA-256: bc58bb402b252ade46eb8e89c6f5c45501b6490f537c612501013cad11a1e40a
154 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The file functions as a link farm, containing numerous URLs pointing to compromised CMS upload directories. These links likely serve to distribute malware or engage in SEO spam. The presence of multiple compromised hosts suggests a broad campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.8273

Heuristics 5

  • 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
  • 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://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/8n90rqcfa86ko09kbvsff82oso/serekibikipavimijex.pdf In PDF document text
    • http://ducthoaudio.com/upload/files/73671396717.pdfIn PDF document text
    • http://pphu-joanna.pl/fckpliki/file/nulurememumigewinenolegu.pdfIn PDF document text
    • https://www.baileysmilk.com/wp-content/plugins/super-forms/uploads/php/files/a090889ca96714b90b49c4749b924b42/12889390850.pdfIn PDF document text
    • https://study4student.com/cache/fck_files/file/5582205116.pdfIn PDF document text
    • http://bjzjygj.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/67176202599.pdfIn PDF document text
    • https://locktactyuma.com/ckfinder/userfiles/files/36323843286.pdfIn PDF document text
    • http://alexandercdg.com/clients/36029/File/29438069239.pdfIn PDF document text
    • http://for-rent-antwerp.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9e418c7c29---navazewunapat.pdfIn PDF document text
    • http://landpas.pl/upload/file/mizofet.pdfIn PDF document text
    • https://www.abaco-engineering.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c5df51a2b58---81800737788.pdfIn PDF document text
    • http://bestorkate.com/uploads/ckeditor/files/miwalesegi.pdfIn PDF document text
    • https://et-auditing.com/userfiles/files/toxerudifageponovonexuz.pdfIn PDF document text
    • http://www.expertnutritionadvisor.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080e60038ed1---90461043136.pdfIn PDF document text
    • http://orem.mn/uploads/files/2420388032.pdfIn PDF document text
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/160916529938b9---kuwaronivapafiru.pdfIn PDF document text
    • https://coastalstudio.com/images/main/file/kewis.pdfIn PDF document text
    • https://baongochoa.com/upload/file/99673650577.pdfIn PDF document text
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7e0da3c8e2---80890593419.pdfIn PDF document text
    • http://swaminarayangm.org/userfiles/file/66909161931.pdfIn PDF document text
    • https://www.penyembuhanholistikreiki.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b4d14254ad2---42653218669.pdfIn PDF document text
    • https://sportli.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160999ff4ef684---mifajakipebivutupek.pdfIn PDF document text
    • http://yule-sign.com/upload/editor/file/20210611174829.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609b7f4f18a58---57632934622.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=treatment+of+optic+neuritis+in+multiple+sclerosisPDF link annotation
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010f79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F79 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1