Malicious PDF — malware analysis report

Static analysis result for SHA-256 91a5a81e3f5314cd…

MALICIOUS

PDF

179.1 KB Created: 2021-08-14 13:27:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 4561506e7201d6160adcb93fd2946643 SHA-1: 4a84070e63c4ca33008678ac854b00f835473b18 SHA-256: 91a5a81e3f5314cd928778703043aea0c31f0bc0a42ab0118cbdd8f383989628
154 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier, with heuristics indicating it functions as a link farm. Multiple URLs are embedded, some pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to malicious content. The PDF structure and embedded links strongly suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9639

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 https://eccdc.org/application/webroot/userfiles/file/96876249127.pdf In PDF document text
    • http://sutphinsgermanshepherds.com/clients/21958/File/70475341354.pdfIn PDF document text
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609581fe97fa6---wumokekixoranevezisanoxup.pdfIn PDF document text
    • http://kadh.kr/bobod/upload/file/keworosepepo.pdfIn PDF document text
    • http://geostudio.eu/userfiles/files/34370730763.pdfIn PDF document text
    • http://hanbangrd.com/userfiles/file/20210809184700_756862514.pdfIn PDF document text
    • https://chetanaus.org/bheru/uploadfiles/file/sijapuloko.pdfIn PDF document text
    • http://metalzilembo.it/userfiles/files/55920870538.pdfIn PDF document text
    • https://copab.tn/216mag.svn/uploads/files/nulefudekuwefo.pdfIn PDF document text
    • https://www.aifimm.it/admin/inc/ckfinder/userfiles/files/fagekivokir.pdfIn PDF document text
    • https://www.pharmaright.ca/wp-content/plugins/super-forms/uploads/php/files/lo7kfma445jsr252ckc9n4mq6g/doziwadonozanadagem.pdfIn PDF document text
    • https://asthasupermarket.com/userfiles/file/91665554392.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160a47c5263b46---sonozemexegi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=creeping+death+2+program+pdfPDF link annotation