Malicious PDF — malware analysis report

Static analysis result for SHA-256 38b670d8b8b8097e…

MALICIOUS

PDF

78.9 KB Created: 2021-06-30 23:46:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 791d4f52ad45d596cb679bb01585ecff SHA-1: 9fd6423d34e918e2cc08b7e75ea59eed4fbb267f SHA-256: 38b670d8b8b8097e39eb37585d31dba29eca7793bb19339df0c43f9868f6b80b
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to compromised CMS upload storage or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, so the primary attack vector appears to be the malicious links within the document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 6

  • 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
  • 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://infrive.ru/uplcv?utm_term=personal+finance+budget PDF link annotation
    • http://stlnsk.ru/uploads/file/sorejin.pdfIn PDF document text
    • http://aisef.org/uploads/userfiles/file/file/devir.pdfIn PDF document text
    • https://accuratesearch.com/userfiles/file/26828569230.pdfIn PDF document text
    • https://muguet.fr/sites/default/files/file/28198355110.pdfIn PDF document text
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/d42def8c27bd92f127247006de049d74/rovidezipude.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160825c6d49ade---68738187338.pdfIn PDF document text
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071c45c77f0d---lolamir.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/5o5k9c3o3bvunk3goec0ccrri6/lisejevozala.pdfIn PDF document text
    • http://csc0731.com/userfiles/file/20210618031552_fk5i5y.pdfIn PDF document text
    • http://nexxosrealty.com/userfiles/files/57345998897.pdfIn PDF document text
    • http://kimyasaldubeller.com/upload/ckfinder/files/tipugepejomed.pdfIn PDF document text
    • http://pocatellocampfire.com/wp-content/plugins/super-forms/uploads/php/files/liur35npboijqg572jsk4h1led/89438378877.pdfIn PDF document text
    • http://www.chicagoalphas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f8d849cb4e---lodosozajup.pdfIn PDF document text
    • http://www.medicellbank.com/userfiles/files/56064086041.pdfIn PDF document text
    • https://oiweld.com/wp-content/plugins/super-forms/uploads/php/files/daf6d29cf06ca41806ba26a4a0584d3f/44678538429.pdfIn PDF document text
    • https://www.eoluk.com/wp-content/plugins/super-forms/uploads/php/files/ha6lf4gjhq1cjcq7iuoqrmedeo/guletivevasata.pdfIn PDF document text
    • https://gyn-koe70.de/obrazky/file/47166619268.pdfIn PDF document text
    • 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_off0000d3a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3A6 10892 bytes
SHA-256: e1818201fccad0ba163edd5a8697cbae1ad286f6a49cd343f6f8a66ca15ec03b
font_01_sfnt_off0000ecc8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECC8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000104da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104DA 16324 bytes
SHA-256: 34bb9d77dd12acee1679154cdf750919099cd9bbe9fb74f6141028d2923bbdb8