Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c8d186c920e6cb1…

MALICIOUS

PDF

78.5 KB Created: 2021-06-25 17:34:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2026-06-05
MD5: 0a5ce99bd89923dc160552e92d7ba993 SHA-1: e3aed14855fd4822ba425bc3b722e9e4055b483f SHA-256: 8c8d186c920e6cb19970e74ee886cf74448d5607d612e37aa00534d41ed57aaf
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to potentially compromised websites, many of which are hosted on disposable domains or use common CMS vulnerabilities. The ML classifier strongly indicates maliciousness, and the structure suggests a link farm designed to redirect users to malicious content. No scripts were extracted, but the overall pattern points to a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

Heuristics 5

  • 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 http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/lk90cep0fb9a2m40794ab6u9f5/2304771126.pdf In PDF document text
    • http://artmetinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072267992a0b---69864591155.pdfIn PDF document text
    • http://oaklandscreche.ie/userfiles/files/tivufilumosefesu.pdfIn PDF document text
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a804f984008---53805656670.pdfIn PDF document text
    • https://htfcompact.com/wp-content/plugins/super-forms/uploads/php/files/23f1509568010b95f1b0b460dcbb1726/26578104745.pdfIn PDF document text
    • https://www.andyselfstorage.co.uk/wp-content/plugins/super-forms/uploads/php/files/jf0cqt58d5m0pjihvoef2n0f0l/gosinetemub.pdfIn PDF document text
    • http://saltokisport.com/uploads/files/depeno.pdfIn PDF document text
    • https://tripleccompanies.com/wp-content/plugins/super-forms/uploads/php/files/25c8ce0b565814e507b9bfaaad89f662/83801378979.pdfIn PDF document text
    • http://midiabyz.com/wp-content/plugins/super-forms/uploads/php/files/45b5c4b85f2ec8a8a5a312f606d5709d/purefunimijanulexusidebiw.pdfIn PDF document text
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb8c2e689c---6686854944.pdfIn PDF document text
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c20b9180260---51898772965.pdfIn PDF document text
    • https://www.napariverinn.com/wp-content/plugins/super-forms/uploads/php/files/fe63252ecc14d13c0f36b78799ee476a/12721703144.pdfIn PDF document text
    • http://drstevealbrecht.com/wp-content/plugins/super-forms/uploads/php/files/521657c7f0093506db4e8e12fa4c3a57/69158473673.pdfIn PDF document text
    • http://campfirewtx.org/userfiles/file/ganidejab.pdfIn PDF document text
    • http://yljx.cn/images/upload/File/57602744019.pdfIn PDF document text
    • https://universal4shipping.net/userfiles/file/tuxonaguboxiwulafosovu.pdfIn PDF document text
    • http://www.rkcomdesignservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160843920dec79---sawesafewulakageditut.pdfIn PDF document text
    • http://r2doodles.com/clients/4/4a/4a4ed909dcef54c1e3ec6a0ce1d29f2d/File/fojumam.pdfIn PDF document text
    • http://www.kindytennis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c50a7a95642---45673318696.pdfIn PDF document text
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6e383d1c29---61062938373.pdfIn PDF document text
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607d195abd2ed---41764601464.pdfIn PDF document text
    • https://olivierdaulte.com/ckfinder/userfiles/files/38620237828.pdfIn PDF document text
    • http://entone.es/wp-content/plugins/super-forms/uploads/php/files/158119d4212607073e32ce6561c11772/kodew.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=why+are+my+pdfs+printing+blackPDF link annotation
    • 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_off0000cdf6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDF6 11284 bytes
SHA-256: 40f58f21bc3ffb34a370aba7e8cc7f788c3c6a36a6ed70e893fb61af072bba0a
font_01_sfnt_off0000e7e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7E0 17324 bytes
SHA-256: fb7d99c3ef0a31342da56c008e9feca0c151558e983d1726bd9b418407c47fdb
font_02_sfnt_off000114eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114EB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1