Malicious PDF — malware analysis report

Static analysis result for SHA-256 99d7ffe221693580…

MALICIOUS

PDF

81.7 KB Created: 2021-08-15 19:29:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-23
MD5: 5319d06bb1888b3c558b09b5d2f38a6e SHA-1: 0334a9408654beb3c749328e71b2798297a6ac32 SHA-256: 99d7ffe2216935806e9bb1ff90969e87f1af9673f2fb27ab9855d00f835cb9f3
204 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file contains embedded JavaScript and multiple external links, many pointing to compromised WordPress sites. The heuristic 'SE_SECURITY_BYPASS' indicates the document instructs the user to disable security software, a common tactic in phishing and malware delivery. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to download and execute a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Security software disable instruction high SE_SECURITY_BYPASS
    Document instructs the user to disable antivirus or security software — unusual for ordinary documents and high-risk in an unsolicited file
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://ecbpolska.pl/wp-content/plugins/super-forms/uploads/php/files/0d1cb0711d1c3e2819e94a9b04cc5992/losesu.pdf In PDF document text
    • http://ofipapel.org//ckfinder/userfiles/files/29618923688.pdfIn PDF document text
    • https://leesman.com/wp-content/plugins/super-forms/uploads/php/files/24c5b5d5550c9382df480be5503d56ac/90308461632.pdfIn PDF document text
    • https://mobistore.co.nz/wp-content/plugins/super-forms/uploads/php/files/e77059bd9cb1f81b450e6ee00600fb9c/lekiwe.pdfIn PDF document text
    • https://vizzzio.ru/wp-content/plugins/super-forms/uploads/php/files/0a2ffe0a8b236392538c0c52a13c35ec/gawoxitufajipug.pdfIn PDF document text
    • http://kokalietudarbnica.lv/files/files/2757098132.pdfIn PDF document text
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/0bcd88a2eb9521f51349002992c1ee70/54970603085.pdfIn PDF document text
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad96bc71b4f---kovaserivip.pdfIn PDF document text
    • https://www.nestroots.com/wp-content/plugins/super-forms/uploads/php/files/n3ctnk08modknphhq7q84ii277/duwazusigazikimigaxofatew.pdfIn PDF document text
    • http://hrzservices.com/uploadfiles/file/96677464861.pdfIn PDF document text
    • https://insights3.com/wp-content/plugins/super-forms/uploads/php/files/35157cd2ec0bab0781595d1c54578d87/fitosokomuvawagasex.pdfIn PDF document text
    • http://acpiindia.com/userfiles/file/niwifemirale.pdfIn PDF document text
    • http://woodlander.sk/grafika/file/kelemedigadiz.pdfIn PDF document text
    • https://parisnordmedical.fr/docs/file/bevega.pdfIn PDF document text
    • https://janeunchained.com/wp-content/plugins/super-forms/uploads/php/files/2bhuh78sqaeknu3vv801h0fcjn/nevenevogepi.pdfIn PDF document text
    • http://maduraicaterers.com/app/webroot/js/ckfinder/userfiles/files/27843891113.pdfIn PDF document text
    • http://vhktn.at/images/content/files/20931391205.pdfIn PDF document text
    • http://wumag.pl/userfiles/file/junat.pdfIn PDF document text
    • http://ikkosushi.com/uploads/files/pokidofopawowufuv.pdfIn PDF document text
    • https://www.propertyfilevault.com/wp-content/plugins/super-forms/uploads/php/files/bc002c6f3f60ae34155777ccf4da454d/wefinulesotapubora.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160ff297c41a44---3880918486.pdfIn PDF document text
    • http://wignaccent.com/FCKeditor_2.6.3/userimages/file/20210708202916.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f9ecd07257---gupiwozikapajuvoj.pdfIn PDF document text
    • http://donateagift.eu/userfiles/file/kinaketuse.pdfIn PDF document text
    • https://galerie-louise.be/userfiles/files/60738581755.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=evaluacion+diagnostica+para+primer+grado+de+preescolarPDF 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_off0000d914.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD914 11004 bytes
SHA-256: 251cf55187fca8204e7521510b3a3825a345decb8e93b657ec1d7d2486a36772
font_01_sfnt_off0000f270.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF270 17448 bytes
SHA-256: 9b0aee9d5e7341e0aa7016731c923d8c7ec997f46eed76439fcb21c2fbf90e27
font_02_sfnt_off00011e78.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E78 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1