Malicious PDF — malware analysis report

Static analysis result for SHA-256 d571b91a9e31322a…

MALICIOUS

PDF

84.8 KB Created: 2021-07-26 12:32:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 568f4e5c2a82dfdfb153303eba65b771 SHA-1: 092cfb2983b127bb2e7c350e21e159f41bcbc620 SHA-256: d571b91a9e31322a4ebef6212e0d2d736e00a2343eecd27d1c1c80cecc7f767b
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample contains embedded JavaScript, a common technique for executing malicious code within PDFs. It also features a link farm pointing to multiple distinct hosts, many of which appear to be compromised WordPress sites, suggesting an attempt to distribute further malicious content or phish users. The ML classifier strongly indicated maliciousness, supporting the assessment of a phishing or malware delivery attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9414

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://www.moyekolodin.com/files/mikuwe.pdf In PDF document text
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/0141c6a054a7ef8b8c97aa01d2674d8a/31375537730.pdfIn PDF document text
    • https://micast.de/wp-content/plugins/super-forms/uploads/php/files/jnfh86htq0ugruuisrcrjro29t/zogiweme.pdfIn PDF document text
    • http://www.justgiveahand.org/wp-content/plugins/formcraft/file-upload/server/content/files/16074260a8c7a3---54281115010.pdfIn PDF document text
    • https://www.traveltimevipp.com/wp-content/plugins/super-forms/uploads/php/files/c8f12cb4b0179273b90fb7172f5c2c93/67502905761.pdfIn PDF document text
    • https://parisautotravel.com/wp-content/plugins/super-forms/uploads/php/files/f2h6pneq8b651f0oabbkigohn5/21647248433.pdfIn PDF document text
    • http://rjt1.org/upload/files/xefope.pdfIn PDF document text
    • https://heykidsletscook.info/wp-content/plugins/super-forms/uploads/php/files/643cad67a7f0148b0b8e4e6dc52ba616/49449662985.pdfIn PDF document text
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/861e56e704f36514301dfb81572bbf32/58900388646.pdfIn PDF document text
    • https://rosewoodcity.org/nbloom/fckuploads/file/vevarojabe.pdfIn PDF document text
    • https://connect.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/1595de7923a47c22db8065c1f8233b42/tezatipafozug.pdfIn PDF document text
    • https://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1608f5de35fe79---fomurud.pdfIn PDF document text
    • https://thepetrichortouch.com/wp-content/plugins/super-forms/uploads/php/files/j1690u5lqn7lqkqg636lsoj5if/13180940408.pdfIn PDF document text
    • https://heuresromantiques.com/upload/files/tizaneporur.pdfIn PDF document text
    • http://andlupa.com/userfiles/file/29690897145.pdfIn PDF document text
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609bc0dacdd34---mukesixetevisimezatipufej.pdfIn PDF document text
    • https://ecomassage.pt/wp-content/plugins/super-forms/uploads/php/files/3ico9qjrq2sfug7s7haln82ld3/97597025739.pdfIn PDF document text
    • http://clairerolo.com/userfiles/file/20224216955.pdfIn PDF document text
    • https://medtek.vn/storage/file/22240084888.pdfIn PDF document text
    • http://anneadamslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/kezabavexosaxulitite.pdfIn PDF document text
    • https://schmitz.cz/res/file/nuxapaxo.pdfIn PDF document text
    • http://alpha-th.com/userfiles/file/8473065676.pdfIn PDF document text
    • http://carnow.jp/js/upload/files/67436754757.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=chapter+13+genes+and+chromosomes+worksheet+answersPDF 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_off0000f50d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF50D 16592 bytes
SHA-256: 7265c0dc20a540fbba5427c89f04a81723222dd5ef8398f58280e46e572676fb
font_01_sfnt_off00012029.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12029 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013840.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13840 11256 bytes
SHA-256: adf452db1ba998081e0f4ecd2703b3d5b5114821a6222ef5f9631bf77bc61fe3