Malicious PDF — malware analysis report

Static analysis result for SHA-256 37657e339b24c591…

MALICIOUS

PDF

80.0 KB Created: 2021-09-01 06:11:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 45a15ab71523a78e2378ac5aa1536272 SHA-1: f7bf6b328b906ef48ff6a231e6d56012bb6aa8a0 SHA-256: 37657e339b24c5914a8503ddcc8e8879cc71ef846e2b31e5894c154e36e28f50
156 Risk Score

Malware Insights

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

The PDF contains a link farm directing to multiple domains, some of which are hosted on compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery. The PDF's structure and numerous external links suggest it's designed to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9887

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
  • 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://amsaneeraus.fi/userfiles/files/xosasil.pdf In PDF document text
    • http://usmleworkout.com/files/file/48671202305.pdfIn PDF document text
    • http://makaeximworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c952ccd25d---sitijuzofexasopiru.pdfIn PDF document text
    • https://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/d088484c155eb6a50e65427fb08f5a48/gutare.pdfIn PDF document text
    • https://yourlightingbrand.com/wp-content/plugins/super-forms/uploads/php/files/758f1553e51d0ca3f7cff3f49c4b48ad/xogivuxusa.pdfIn PDF document text
    • https://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/1bc36ac860ad7aab34f7a4bedc73a70b/22963301122.pdfIn PDF document text
    • https://rmp-familienanzeigen.de/cms/files/49717429354.pdfIn PDF document text
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070fb130b224---69955735496.pdfIn PDF document text
    • http://soft-pro.hr/upload/datoteke/13072571030.pdfIn PDF document text
    • https://www.fmworks.com.tr/wp-content/plugins/super-forms/uploads/php/files/64p8k0mo9sv938u3hbd728t0kk/82501287468.pdfIn PDF document text
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad8f27142fe---49194213127.pdfIn PDF document text
    • http://ar-intl.net/wp-content/plugins/super-forms/uploads/php/files/26j7ht4d5g5hnffb6qm3vgjbf6/setukag.pdfIn PDF document text
    • http://trustycctv.com/ckfinder/userfiles/files/15742134501.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/161039b360806f---16979465568.pdfIn PDF document text
    • http://consade.com/userfiles/file/lokotedovesekuvuraged.pdfIn PDF document text
    • http://isspskola.lv/userfiles/files/wivebonifubifituxira.pdfIn PDF document text
    • http://ugyvednok.hu/userfiles/file/nakakat.pdfIn PDF document text
    • http://ahsaipu.com/v15/Upload/file/2021522054302749.pdfIn PDF document text
    • http://novafish.it/userfiles/files/78707122444.pdfIn PDF document text
    • http://grapes4u.ca/sites/all/sites/grapes4u.ca/files/20062555444.pdfIn PDF document text
    • https://lakeshoresmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/7cbcq75f60tduu0qv5c9qmdg67/dupewokosovo.pdfIn PDF document text
    • https://artgreen.vn/attachment/files/8700843023.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=chicken+meatball+soupPDF 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_off0000e015.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE015 17748 bytes
SHA-256: a9f250410eb6859faa710a46f9249421a0d80f1c9b5661234f42f92c25ffc108
font_01_sfnt_off00010e10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E10 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012627.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12627 10904 bytes
SHA-256: f5cf47ff225408db57be9d021e7707cdcfcc9c54917b16eca7d7757c6d3f6be9