Malicious PDF — malware analysis report

Static analysis result for SHA-256 e573b7c355adad87…

MALICIOUS

PDF

72.1 KB Created: 2021-09-02 05:11:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 65ba2b520395e72dc80b353d91ed1c59 SHA-1: 96f63d2311a829e54ea7dc7045cbb2cd132d4577 SHA-256: e573b7c355adad873feef625ea4eb918e9cfdf2e41e705c1b163786a87ab1d9b
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to compromised CMS upload directories and disposable hosting, suggesting an attempt to distribute malicious content or phish users. The embedded URLs, while some are marked benign, contribute to the overall pattern of directing users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6661

Heuristics 5

  • 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
  • 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.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/16110debd8fe4e---81333719614.pdf In PDF document text
    • http://biolabsrl.org/userfiles/files/36706615843.pdfIn PDF document text
    • http://huile-de-nigelle.info/userfiles/file/72844846898.pdfIn PDF document text
    • https://www.harnoordesigns.com/wp-content/plugins/super-forms/uploads/php/files/66bf84ac4784c8d05d1ce28d10dbc0b6/96533810455.pdfIn PDF document text
    • http://vilaportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac2f1d62975---50017638125.pdfIn PDF document text
    • http://kimhoatra.vn/upload/fckimagesfile/tomovozujulutivuno.pdfIn PDF document text
    • http://baobiachau.com/luutru/files/85856187698.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6a202d5989---56330664400.pdfIn PDF document text
    • https://mamalight.net/business_school/uploads/file/luxuritosivezubenowepujax.pdfIn PDF document text
    • https://proxus.nl/file/dedisosax.pdfIn PDF document text
    • https://flyags.com/editorResources/file///vukagajidajefajifufedupa.pdfIn PDF document text
    • https://asiaviews.org/wp-content/plugins/super-forms/uploads/php/files/ptkikeptj1tuos1q62ho341it1/jizor.pdfIn PDF document text
    • https://yomadesign.com/userfiles/Proj_Name/files/makoxavozoviduvinoke.pdfIn PDF document text
    • http://veoguidecostarica.com/ci/userfiles/files/ninabogiv.pdfIn PDF document text
    • http://csc0731.com/userfiles/file/20210721141706_9g1eni.pdfIn PDF document text
    • http://shahnawazonline.com/uploads/files/nunawunilifurumab.pdfIn PDF document text
    • https://rmdschoolandcollege.com/wp-content/plugins/super-forms/uploads/php/files/21uhdakuk1g9hl99361gpcka80/19307899873.pdfIn PDF document text
    • http://poliinc.com/upload/files/84398081184.pdfIn PDF document text
    • http://interel-rus.ru/test/sites/default/files/file/zuvovuparizo.pdfIn PDF document text
    • https://mides.vn/images/ckeditor/files/41622646844.pdfIn PDF document text
    • http://locke-3c.tw/uploads/files/202108170757358889.pdfIn PDF document text
    • https://beribuket.ru/wp-content/plugins/super-forms/uploads/php/files/19c742beaba8020d671e2a66abb902f5/49399176732.pdfIn PDF document text
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090958cdcf20---midamejepamajopelekegidi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=write+down+the+chemical+equation+of+photosynthesis+in+plantsPDF link annotation
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d3a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3A3 11324 bytes
SHA-256: 06be319fa78368bf08160aa9452f17e7e1ed4b4dee0442ed1f96d0a94cb0b101
font_01_sfnt_off0000edec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDEC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1