Malicious PDF — malware analysis report

Static analysis result for SHA-256 98289663d40c6e31…

MALICIOUS

PDF

90.5 KB Created: 2021-10-23 15:33:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: b0535850086fb4fc0684d34c9bc583bc SHA-1: dbf02f08a6b56cf917846bf6ee8134a665bf131b SHA-256: 98289663d40c6e31c3d4272f8eddf7cff03a084da410bf69a9c213f85b79c851
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file detected as malicious by ClamAV and an ML classifier, containing embedded JavaScript. It also functions as a link farm, with many URLs pointing to other PDF files hosted on various domains, some of which are identified as compromised CMS uploads. This suggests a multi-stage attack, likely involving phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://postelezmasivu-praha.cz/ckfinder/userfiles/files/lipemamalebizu.pdf In PDF document text
    • https://tranhtreo.com/images/ckeditor/files/pidonuv.pdfIn PDF document text
    • https://corumosmanlimakina.com/js/ckfinder/userfiles/files/fiberuwa.pdfIn PDF document text
    • http://shannonlakeestates.org/fck_images/file/gigolijalijananuj.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161438ea92e6f9---mekometudafolivefotegami.pdfIn PDF document text
    • http://robertoantoniz.com/resources/original/file/9336965469.pdfIn PDF document text
    • http://wpklaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/newitekixamajafobo.pdfIn PDF document text
    • http://ministryofrum.com/memlogos/file/26399335925.pdfIn PDF document text
    • https://asaptransfers.co.uk/wp-content/plugins/super-forms/uploads/php/files/e4446eec74f8a6fd0a871f53a6bb8df0/ritipadiwalo.pdfIn PDF document text
    • http://dreesmann-foto.de/userfiles/file/lotiginekokutosu.pdfIn PDF document text
    • https://broadcasthub.com/ci/userfiles/files/9352850064.pdfIn PDF document text
    • https://vakukh.ru/wp-content/plugins/super-forms/uploads/php/files/8a0e14fbbf9e5c944aca7335f5dd50a0/13515757075.pdfIn PDF document text
    • http://antwerp-rentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/16173311c071de---rukefafusapojanupevebawa.pdfIn PDF document text
    • https://ykitraders.com/UserFiles/file/jawuzabaw.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/42629cd95d7d6d7b2cb96afdcadf1c61/40290156110.pdfIn PDF document text
    • http://espwireless.net/uploads/file/63244251918.pdfIn PDF document text
    • http://meteosputnik.ru/userfiles/file/madifuvupojaxune.pdfIn PDF document text
    • https://haltia.mx/sii/ckfinder/userfiles/files/lasolunu.pdfIn PDF document text
    • http://tasarimak.com/ckfinder/userfiles/files/kugudetomebalolot.pdfIn PDF document text
    • http://khonggianmang.com/upload/files/kosapupizigusegosedutal.pdfIn PDF document text
    • https://lawtutors.co.uk/js/ckfinder/userfiles/files/kedadomekedujebuperunob.pdfIn PDF document text
    • http://rubivina.com/Images_upload/files/28622676465.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Gsjc/~3/HKUGBsJGI0E/uplcv?utm_term=structuralist+perspective+psychologyPDF 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_off0000fb69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB69 10904 bytes
SHA-256: 04ac5ed80ee4bed03be236c803f69e54b02c7080e1a08be6239827e94c020fff
font_01_sfnt_off000114cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114CF 18068 bytes
SHA-256: d7e7673a658ac7a42839df1cd173a1e383cbf7098517812fe3bc626c516587e2
font_02_sfnt_off000143ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x143EF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1

Open this report in the interactive analyzer, or submit your own file for analysis.