Malicious PDF — malware analysis report

Static analysis result for SHA-256 66a6fb0a68b00346…

MALICIOUS

PDF

88.3 KB Created: 2021-06-11 08:20:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 19bd46ba35a156573542734c40b94eab SHA-1: 94d2c5b753d4c1cbcc5923e58891afd658c68bd0 SHA-256: 66a6fb0a68b0034626fd7ef41deba17bcb4c2fe578b301427c9c925e2df16086
156 Risk Score

Malware Insights

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

The PDF file contains numerous links to external websites, many of which are hosted on compromised WordPress sites. The presence of a ClamAV detection for 'Pdf.Phishing.Trojan' and ML classification strongly indicates malicious intent. The document body, though heavily obfuscated, suggests a lure related to 'concise biology class 9 pdf download', aiming to trick users into accessing malicious URLs that likely serve further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://pixomot.ru/uplcv?utm_term=concise+biology+class+9+pdf+download PDF link annotation
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609de591c8b8a---pemomedesesikebojetirob.pdfIn PDF document text
    • https://humanistbeauty.com/wp-content/plugins/super-forms/uploads/php/files/bf4bofbmq7ur0o0kci4e2sae43/30270830295.pdfIn PDF document text
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607c47d11d0ff---rebejuwan.pdfIn PDF document text
    • http://ukrainski-rosyjski.pl/userfiles/file/waxamomimoduwurug.pdfIn PDF document text
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/16082b5a2c6256---fifimepipukazabibudepate.pdfIn PDF document text
    • https://nocenzura.space/web/img/podborky/files/92192374784.pdfIn PDF document text
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079199772d66---jatopotigenezinuredobizu.pdfIn PDF document text
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/47585aa5a01cb3e724e13f32f9dc027d/16119576494.pdfIn PDF document text
    • https://purebodycare.courses/wp-content/plugins/super-forms/uploads/php/files/svf8b4gdun222ulph1ima7pjd6/96316358181.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c8746661fc---58647167156.pdfIn PDF document text
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/22092b7a4e47ab16c55ed9459f789695/62657484545.pdfIn PDF document text
    • http://jjinline.org/file_upload/file/zofiw.pdfIn PDF document text
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1609172111eb86---53631092745.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://fedorahosted.org/lohitIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001116e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1116E 5620 bytes
SHA-256: af4ae8b43812be9ab70333401e238d1935d94a15b7849260c95d9a84a295412c
font_01_sfnt_off000124b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124B4 10756 bytes
SHA-256: 4c2f3661e075f4312e48b1fcf9207dd938a5e81344ba2f1cac508a198c9fdf4f
font_02_sfnt_off00014946.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14946 2704 bytes
SHA-256: 301b25a1c800571e564dd8343569d726410c81a3633851d420d08300fd17c00e