Malicious PDF — malware analysis report

Static analysis result for SHA-256 99e30edbbe1b9144…

MALICIOUS

PDF

79.5 KB Created: 2021-09-08 17:34:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 42d63e6e77a973b42c5c290ae077bcc0 SHA-1: 98c0a939ca6855b888b9eb91d943847a36dba44d SHA-256: 99e30edbbe1b9144c8c3edc51e5f0a3e0677c211f40f694acdc040100893cb52
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was identified as malicious by both ML classification and ClamAV, specifically flagged as a phishing trojan. Analysis revealed it functions as a link farm, containing numerous URLs pointing to potentially compromised websites or disposable hosting, disguised as a download link for a novel. The presence of these links and the overall structure strongly suggest an attempt to lure users into clicking through to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://danfort.lv/userfiles/file/14235524293.pdf In PDF document text
    • http://thesei.com/In PDF document text
    • https://www.poolsrus.com.au/application/third_party/ckfinder/userfiles/files/66131009724.pdfIn PDF document text
    • http://jinwoosmc.com/userfiles/file/27482638295.pdfIn PDF document text
    • http://professionalcatererspaul.pageindia.com/resume/cms_files/files/235525460.pdfIn PDF document text
    • https://businesslife.com/content/files/7338055571.pdfIn PDF document text
    • http://klubalfa.org/img/userfiles/file/gakosotimomanelukapide.pdfIn PDF document text
    • http://brukbet.com/user_images/file/kenurenebowupenap.pdfIn PDF document text
    • http://czernavendeghaz.hu/admin1/file/51863796672.pdfIn PDF document text
    • https://tabularasa.lv/sites/tabularasa/uploads/documents/files/95273656091.pdfIn PDF document text
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/161337973d4636---52340249457.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1612f36540ea1d---terazajiv.pdfIn PDF document text
    • http://dom-2000.ru/ckfinder/userfiles/files/26617150577.pdfIn PDF document text
    • http://robvancampen.nl/userfiles/file/98652588945.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/863674744b25deabebc054af37b10613/kozipidolasek.pdfIn PDF document text
    • http://uralcomservis.ru/crn_fls/crn_files/wabonabupexod.pdfIn PDF document text
    • http://maychaybocaocap.com/app/webroot/uploads/files/35227350103.pdfIn PDF document text
    • http://miroslaws.com/ckfinder/userfiles/files/rexevepotobusamekukeku.pdfIn PDF document text
    • https://chokysitohang.com/Uploads/userfiles/files/33606329190.pdfIn PDF document text
    • https://renteci.com/imagens/file/77731026829.pdfIn PDF document text
    • http://ntep2008.com/UserFiles/File/pifesubirurul.pdfIn PDF document text
    • http://pooq-design.com/app/webroot/fckfiles/file/45199354584.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612e99b32ae80---1408172370.pdfIn PDF document text
    • http://bushurov.ru/images/files/66406453695.pdfIn PDF document text
    • http://viprealestatebrokers.com/userfiles/files/bidup.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=download+novel+arifureta+pdfPDF 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_off0000cf07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF07 18784 bytes
SHA-256: 7665d3850bdbe272e8ab3e9526f1897161cddf3090f097a4349cd60c6ae8a254
font_01_sfnt_off00010042.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10042 10576 bytes
SHA-256: 2ee439803b58aae597b148579ccac74603ffd9e67891c448957f29c862ed4298
font_02_sfnt_off00011887.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11887 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1