Malicious PDF — malware analysis report

Static analysis result for SHA-256 91be4ed20b2bb328…

MALICIOUS

PDF

70.9 KB Created: 2021-09-12 03:01:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 0f65755c798cb33e9c374d7cf2c80180 SHA-1: 716b1be8c0619e4b6e918101c87ee60675991103 SHA-256: 91be4ed20b2bb328fe7408a4fb2285f1dd81901e36ed37d9e551c5fdffe70149
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm directing to multiple external URLs, many hosted on compromised or disposable domains, indicating a phishing or malware distribution attempt. The ClamAV detection and ML classifier strongly suggest malicious intent. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://owop.challengersports.com/ckfinder/userfiles/files/zumoruwazegopajapugalum.pdf In PDF document text
    • http://weiddy.com/uploads/files/202109082342369850.pdfIn PDF document text
    • http://www.ondebiz.com/userfiles/file/fanuzalibigugener.pdfIn PDF document text
    • https://spherule.org/wp-content/plugins/super-forms/uploads/php/files/cf8e98sasfl86cvivnokhabt34/nepozolawupatisuwoz.pdfIn PDF document text
    • http://sporteambiente.it/ckfinder/userfiles/files/63514521255.pdfIn PDF document text
    • https://frisch.ro/files/file/67911692478.pdfIn PDF document text
    • http://hopkim.vn/upload/files/37488971970.pdfIn PDF document text
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/16138670278747---93673753691.pdfIn PDF document text
    • http://importfoodfair.com/userfiles/image/2021/09/file/94864002729.pdfIn PDF document text
    • http://franklcalabreseattorney.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/lumil.pdfIn PDF document text
    • http://e-district.org/userfiles/file/78674041069.pdfIn PDF document text
    • https://girl0229960192.com/upload/users/files/22003217274.pdfIn PDF document text
    • http://baheth24aqari.com/ckfinder/userfiles/files/lusotozujoxofarinuvimof.pdfIn PDF document text
    • https://www.penyembuhanholistikreiki.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cb61753762---duzilupigetixagafu.pdfIn PDF document text
    • https://perfecthospitals.com/ckfinder/userfiles/files/23506493171.pdfIn PDF document text
    • https://korvioinfotech.com/ckfinder/userfiles/files/liwagijibejolodonatijalo.pdfIn PDF document text
    • http://runnersavezzano.it/public/userfiles/file/33670125344.pdfIn PDF document text
    • https://estduquebec.com/scripts/php/xenocode/lib/ckfinder/userfiles/files/dikepojumedopulidotuvonuv.pdfIn PDF document text
    • https://pianotuningdarwin.com/userfiles/files/witakijugibip.pdfIn PDF document text
    • http://orikon.net/Images_upload/files/lebabebowijesegupukub.pdfIn PDF document text
    • https://tadimtursu.com/image/files/gipeda.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=multi+sms+sender+apkPDF 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_off0000b2ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2EA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cb01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB01 10620 bytes
SHA-256: 0ed3d13040050de43cf957e751d2ce6ef03ac2679dbb5653f6dfb2e10f384b56
font_02_sfnt_off0000e339.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE339 16728 bytes
SHA-256: 70ed6a8b007cc8f163a4f63ba75809cb8a31a5f78ce0187d236901ef96955ea5