Malicious PDF — malware analysis report

Static analysis result for SHA-256 27f941900abaf16c…

MALICIOUS

PDF

80.4 KB Created: 2021-09-01 19:33:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: da9cab3c3f5c08a4e9bab4bbfa1ce74b SHA-1: 052fe1d830342914780010469e9a899ebccf2928 SHA-256: 27f941900abaf16c779c57710a88680010e660a9010fb4560cc3816760cca340
156 Risk Score

Malware Insights

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

The PDF was flagged by multiple heuristics, including ClamAV and an ML classifier, as malicious. It contains a link farm pointing to compromised WordPress upload storage and other disposable hosting sites, suggesting an attempt to redirect users to malicious content. The presence of external URIs and compromised CMS upload links indicates a likely phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6941

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 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
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PDFSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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://internationalnetworksolutions.net/files/ In PDF document text
    • http://ilovegabal.net/fckeditor/_upload/file/97703416589.pdfIn PDF document text
    • http://jocoseatee.com/userfiles/files/kudagikexakamu.pdfIn PDF document text
    • https://ev-owners.jp/userfiles//files/nonorefuna.pdfIn PDF document text
    • https://bikeid.net/ckfinder/userfiles/files/76425176540.pdfIn PDF document text
    • http://ski-experience-japan.com/images/blog//file/35137582350.pdfIn PDF document text
    • http://parquessolaresdenavarra.com/userfiles/files/73643425751.pdfIn PDF document text
    • https://uniqrelation.com/userfiles/file/9958390058.pdfIn PDF document text
    • http://giasuthanhdat.vn/Images_upload/files/18977954068.pdfIn PDF document text
    • http://www.prieteniitehnicii.ro/documente/file/rajojofenupavusewe.pdfIn PDF document text
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/e5cc80209e39ab885f947c9a2230d118/negosowoxuxigakevija.pdfIn PDF document text
    • http://famcareconnect.org/wp-content/plugins/formcraft/file-upload/server/content/files/16095e02c2175e---vozolodizefidobibab.pdfIn PDF document text
    • http://tsradviseurs.nl/mailing/images/photo/file/bewifuzorirogivo.pdfIn PDF document text
    • https://torgradio.ru/new/files/file/34937428074.pdfIn PDF document text
    • http://turnyras.lt/Files/file/19365180831.pdfIn PDF document text
    • https://yourtuscanyguide.com/wp-content/plugins/super-forms/uploads/php/files/2etlj7q7cicftod0me98nhqan3/musawolekug.pdfIn PDF document text
    • http://ezstreetautosales.com/clients/876244/File/46152520150.pdfIn PDF document text
    • http://fishtech.org/uploads/userfiles/file/file/68406767724.pdfIn PDF document text
    • http://cascinamana.it/userfiles/file/lobumazepalovalan.pdfIn PDF document text
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be75bf69cc9---farisefose.pdfIn PDF document text
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c99707e7b0f---winexedasetow.pdfIn PDF document text
    • http://huichem.com/ckfinder/userfiles/files/97238933927.pdfIn PDF document text
    • http://historico.uts.edu.co/portal/app/ckfinder/userfiles/files/89173308767.pdfIn PDF document text
    • https://nhaccugiare24h.com/uploads/userfiles/file/53309809361.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=very+well+likedPDF link annotation
    • 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_off0000d802.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD802 9848 bytes
SHA-256: 55ea651f452e1561526635d9b51b08b74838bbbff680dc5799674909c03842d3
font_01_sfnt_off0000edb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDB8 21424 bytes
SHA-256: e0cfd340fe93d041daee8e1648faaa7e03eb0d22c15578387aa679ab249c4b7c
font_02_sfnt_off0001259c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1259C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1