Malicious PDF — malware analysis report

Static analysis result for SHA-256 04cd76178ee02463…

MALICIOUS

PDF

75.6 KB Created: 2021-09-19 11:06:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: b2d1b5ed56c5df01b539ad75252a30dc SHA-1: f28a32e08db52aa958f33ab96c20f5ca9abcbcd0 SHA-256: 04cd76178ee024631f2692fef92bf01f35f8077755f6cf5f49a242ff7d4f519f
164 Risk Score

Malware Insights

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

The sample is a PDF file detected as malicious by ClamAV and an ML classifier. It contains embedded JavaScript and a link farm pointing to multiple compromised WordPress sites and other domains, suggesting an attempt to lure users to malicious content. The presence of embedded JavaScript indicates potential for further malicious actions beyond simple redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/9mdclup9i196vbi5dmavqhb9qv/fuvivavupepaniguxuwomagi.pdf In PDF document text
    • http://paroissedementon.fr/upload/files/97104708161.pdfIn PDF document text
    • https://nestsearch.in/admin/uploads/file/21880931679.pdfIn PDF document text
    • http://aftp.bg/userfiles/file/31941894578.pdfIn PDF document text
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/16144b1dd4dcd1---45210793294.pdfIn PDF document text
    • https://fobh.net/userfiles/files/fijelawunux.pdfIn PDF document text
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b78e5373d1---33407842981.pdfIn PDF document text
    • https://premiersuli.hu/files/files/59099738065.pdfIn PDF document text
    • http://cinebuzz.be/uploads/userfiles/files/93200416129.pdfIn PDF document text
    • http://mdbim.pl/ubezpiecz/obrazy/file/21580398620.pdfIn PDF document text
    • http://ngocphuocjsc.com/public/default/ckeditor/files/89488207868.pdfIn PDF document text
    • http://cozycornerexpress.com/uploads/files/97763652483.pdfIn PDF document text
    • https://deltarents.com/upload/ckfinder/files/91352196286.pdfIn PDF document text
    • https://xn--espaoldetalca-lkb.cl/var/www/html/upload/file/nedosimumogiguzoteb.pdfIn PDF document text
    • https://codefon.hu/js/ckfinder/userfiles/files/muzibatusikisuxuto.pdfIn PDF document text
    • http://xinxinhouseware.com/uploadfile/files/diverukovimimetalazawox.pdfIn PDF document text
    • http://www.jacenter.org/js/ckfinder/userfiles/files/sibowemuditote.pdfIn PDF document text
    • http://conflictfreeelectronics.com/ourprojects/chowki/UserFiles/renuka/file/lufex.pdfIn PDF document text
    • http://sity-luxe.ru/userfiles/file/46419766459.pdfIn PDF document text
    • http://akilanews.com/ckfinder/userfiles/files/12048148264.pdfIn PDF document text
    • http://hongdacable.com/d/files/sotodolefukaxupofarawofi.pdfIn PDF document text
    • http://jonme.net/ckupload/files/81114554314.pdfIn PDF document text
    • http://yaan121.com/uploads/files/202109140751032328.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=sexy+video+calling+app+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://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_off0000c4b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC4B4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dcc6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCC6 16724 bytes
SHA-256: 17fd4f8d4b6c63c09c9259da161c2dfcfeb17181aa550d3cfd28bc332815d55a
font_02_sfnt_off000107f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107F4 10764 bytes
SHA-256: 37c86683f5981a0b79cec14546b97356421e0e5c7c931dde960df68828c76253