Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef9089e2dd057fe8…

MALICIOUS

PDF

69.5 KB Created: 2021-06-24 11:05:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-26
MD5: 7988efdf3aff339fed394781175be7c2 SHA-1: 485c722a9a0bfb87707efa58ea220123de0d75f0 SHA-256: ef9089e2dd057fe811c9fe73625926746fc80a4ea4c38066ca6ab4aa40a9b5ee
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF contains embedded JavaScript, which is often used to redirect users to malicious sites or download further payloads. The heuristics indicate the document is part of a link farm hosted on compromised WordPress sites, attempting to trick users into downloading a file by appearing to offer a book download. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 7

  • 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.
  • 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
  • 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://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/160d288b793fd4---mijikaminebetibo.pdf In PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/gk7qm6h8ubtd3uct70o3fm1k8c/zudokisuzaku.pdfIn PDF document text
    • http://waterreducer.cn/d/files/22237003750.pdfIn PDF document text
    • http://eros-arena-reutlingen.de/eros/userfiles/file/2529354305.pdfIn PDF document text
    • http://www.blackhillsdancecentre.com/wp-content/plugins/formcraft/file-upload/server/content/files/160842f9ec7961---87460112544.pdfIn PDF document text
    • http://shs1977reunion.com/clients/41590/File/4402375089.pdfIn PDF document text
    • https://i-chat.tw/js/ckfinder/userfiles/files/31225886427.pdfIn PDF document text
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16085b9b7b4837---24628415924.pdfIn PDF document text
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160848f5e927b7---depuxujutenewogesulenono.pdfIn PDF document text
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160742f81276b1---fiwidilibuvuseda.pdfIn PDF document text
    • https://www.nexidia.it/wp-content/plugins/super-forms/uploads/php/files/96715fc254aa5c95622c26e919a905a4/daxelasarupexuroxik.pdfIn PDF document text
    • http://www.canadavisaservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608bdfc369777---vawagokejigenilolumego.pdfIn PDF document text
    • https://refour.eu/wp-content/plugins/super-forms/uploads/php/files/a85b14e7445ebe29bafc6c82eccb72fc/foguworikuja.pdfIn PDF document text
    • http://takeacode.net/user/d41d8cd98f00b204e9800998ecf8427e/file/81333705822.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=tony+buzan+use+your+head+pdf+downloadPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c818.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC818 5464 bytes
SHA-256: 413b561547780562c4401d72a74ddd3789bbfafea50a3b64c56926fbec306c09
font_01_sfnt_off0000dabc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDABC 21312 bytes
SHA-256: 39f0c599174ca4aa8b45c8b51ec1ec3166ee64deefda00097ae176374db3a432