Malicious PDF — malware analysis report

Static analysis result for SHA-256 43b63e42f68a31f6…

MALICIOUS

PDF

64.2 KB Created: 2021-06-19 07:38:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 08786187590113d193371b2fa3404b55 SHA-1: db261fae37925977cad904bd79cb4d7ff89acf47 SHA-256: 43b63e42f68a31f6db965f26d130364793b662fb22604db4c44a777cacf688fe
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains a link farm pointing to compromised WordPress sites and disposable hosting, suggesting an attempt to redirect users to malicious content. The document body is heavily obfuscated, but the presence of embedded URLs and the nature of the heuristics indicate a phishing or malware distribution attempt.

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://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/d5136a5afb5b25cc2bec4d24ff357373/65146146732.pdf In PDF document text
    • https://bhiringisamsankalimandir.org/ckfinder/userfiles/files/baribewikafefor.pdfIn PDF document text
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b615bc6a59---vobugal.pdfIn PDF document text
    • http://smithmurdock.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073cb7519d97---bexikigimitefofarere.pdfIn PDF document text
    • http://bezpiecznamlodosc.org/files/file/gudamobasibavile.pdfIn PDF document text
    • https://cosalesrep.com/wp-content/plugins/super-forms/uploads/php/files/e29896fe66b6a5936519b0522b3cfe32/99994577263.pdfIn PDF document text
    • http://cfh2.com/clients/d/d2/d2a7b52150a7a947468b52e9b7560e3c/File/nawubazavijepisowojebe.pdfIn PDF document text
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608168ad9e3ed---89394763216.pdfIn PDF document text
    • http://berbun.com/user_img/file/2073779397.pdfIn PDF document text
    • http://mikailang.net/userfiles/file/20210522055126_1499100684.pdfIn PDF document text
    • http://aisef.org/uploads/userfiles/file/file/vanizekupo.pdfIn PDF document text
    • http://sodrex.pl/userfiles/file/27425190498.pdfIn PDF document text
    • https://foxtailmag.net/wp-content/plugins/super-forms/uploads/php/files/459e9ddb51824f040da99dcc3066f3c4/41868725831.pdfIn PDF document text
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609e7a3e80c15---49319153532.pdfIn PDF document text
    • https://houstoncoinshow.org/FCKeditor/file/bogemawixozove.pdfIn PDF document text
    • https://nscs.org/wp-content/plugins/super-forms/uploads/php/files/0fe68e37c011bc69a86f53fd9af404e8/91759432358.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/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=icivics+banks+credit+and+the+economy+answersPDF 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_off0000bc81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC81 5544 bytes
SHA-256: b448d2a0f39c3e4da810da5ecbb1ead1c5972d056a28f940d236ab62e81bb1fc
font_01_sfnt_off0000cf4b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF4B 10192 bytes
SHA-256: 9845d5777c435d7fb61b47a752141f42c9e66cfb20b40e5cd7b29e5f7bc31506