Malicious PDF — malware analysis report

Static analysis result for SHA-256 66cb3dba80e7b94f…

MALICIOUS

PDF

237.6 KB Created: 2021-06-28 12:53:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 41fbb34c0a80d8e8530302b7bfa32028 SHA-1: 2229a61916de9d981e51f29c88064b1f953ff3e3 SHA-256: 66cb3dba80e7b94f6384373a6de9cb5c929beccce19f8679dccd8a929e08a4c8
166 Risk Score

Malware Insights

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

The PDF contains multiple heuristics indicating it is a phishing lure, including a link farm and an SEO redirector pointing to a compromised WordPress upload. ClamAV also detected it as 'Pdf.Phishing.Trojan'. While no scripts were directly extracted, the structure and embedded URLs suggest it is designed to lead the user to a malicious resource, likely for further exploitation or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9946

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
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • 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.
  • 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://cornerstonelaw.eu/userfiles//file/54254860206.pdf In PDF document text
    • https://ethiquedevelopers.com/wp-content/plugins/super-forms/uploads/php/files/dcbe3dac8339ae3f14e63b9e9ceed3d9/60724905835.pdfIn PDF document text
    • http://debandhelder.nl/ckfinder/userfiles/files/30320028302.pdfIn PDF document text
    • http://www.siscbolivia.com/admin/uploaded/fck/file/82572821226.pdfIn PDF document text
    • http://usaoxin.com/userfiles/2021-5/file/mumovumupenikewilewofa.pdfIn PDF document text
    • https://binarbaidfabrication.com/public_html/userfiles/file/92793126942.pdfIn PDF document text
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f05bd9dcc9---91235736921.pdfIn PDF document text
    • http://jpind.pl/userfiles/file/kojaruxu.pdfIn PDF document text
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/160795ef1e0e8c---50529533467.pdfIn PDF document text
    • http://aliceinformaticasrl.com/user/pages/98291019674.pdfIn PDF document text
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160a2172cce660---41778374697.pdfIn PDF document text
    • https://www.deuba.info/wp-content/plugins/super-forms/uploads/php/files/kqht17e61j1cihnb6s2v9put4c/xodak.pdfIn PDF document text
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160788f7ea91e7---24980453092.pdfIn PDF document text
    • https://108pizza.pl/uploads/userfiles/files/16451907266.pdfIn PDF document text
    • http://webinside.pl/userfiles/file/19094883559.pdfIn PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/16093b8115de91---juguxutopujupafuv.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=read+the+text+below+and+choose+the+correct+answerPDF link annotation
    • http://s292376414.onlinehome.fr/datas/imgmail/file/49379027569.pdfIn 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000320a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x320A2 10748 bytes
SHA-256: c63c9aac6a94f95dcf414ba2a4dd98a59dee6c6df1d5243b67a0dd9ce57e4ee2
font_01_sfnt_off00033955.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x33955 16204 bytes
SHA-256: 2f37ea1b11ece644fef2f420fc5d5e29c860255d372ec3a711666e2589675489
font_02_sfnt_off00034f07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x34F07 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off00036719.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x36719 27420 bytes
SHA-256: 866e5dd6ea6ce1b374692556102bde256b0aff971656326882e29483bbb83e58