Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b85e72fd152572f…

MALICIOUS

PDF

72.6 KB Created: 2021-06-22 10:36:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: bbe6a646d07e3f296d1a8d339e3d1764 SHA-1: 68b71764211cf766608f2d539a441fc99e5dbc61 SHA-256: 3b85e72fd152572fdd3ba1d1de4e6eb72b470fae098db68d425519d5d30722e9
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by multiple heuristics and a machine learning classifier. It functions as a link farm, containing numerous embedded URLs that point to compromised WordPress installations and other potentially malicious sites. The primary purpose appears to be directing users to external resources, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://catamma.ru/uplcv?utm_term=sodium+fluoride+ionic+or+covalent PDF link annotation
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/160743dc6252f6---mutat.pdfIn PDF document text
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b51b3c4192---85375093900.pdfIn PDF document text
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607c7b9602b67---mifewix.pdfIn PDF document text
    • https://www.chartsunlimited.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/160866f812ffd3---wurejabadirexufinomazedu.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b26b844b730---43286781579.pdfIn PDF document text
    • https://personnelcle.com/userfiles/file/wajivefovixexaragip.pdfIn PDF document text
    • https://handientu.vn/userfiles/file/97292431392.pdfIn PDF document text
    • http://lynhuagiasi.com/Images_upload/files/lamag.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/63e2c6a78a0b0fb2ef190842d7a390e4/25278284113.pdfIn PDF document text
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080b284c0734---80174040634.pdfIn PDF document text
    • https://investainternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e8295df31e---49782633070.pdfIn PDF document text
    • http://aprendanow.com/wp-content/plugins/super-forms/uploads/php/files/981290f99b706e6cb5aebb99de3586aa/97298104640.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b95dbeba0d---lexowagikixenilo.pdfIn PDF document text
    • https://communeouchamps.fr/userfiles/file/46244993996.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b842ea53de0---virofevexavoxawulufobom.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dcb4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCB4 5152 bytes
SHA-256: 955c0d181705cfe9433cc329887239ea156801259348acfb7f80f6da4dd3d78b
font_01_sfnt_off0000ee2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE2D 11596 bytes
SHA-256: 8078a047e7f561469188ab687462b95fe8d3eeac7ccd3d450206e3fb5108513a