Malicious PDF — malware analysis report

Static analysis result for SHA-256 76bf2ea0bb459cc6…

MALICIOUS

PDF

87.4 KB Created: 2021-07-23 02:30:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: e3cd7cf15a9fb9b1b8d211b56c944de0 SHA-1: a076adcd503ae9cd81212440dda05591b2ef638e SHA-256: 76bf2ea0bb459cc659d93dcd0ed5459539317c519a1ec37e1840e37afe14cd87
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The presence of embedded JavaScript and multiple heuristics indicating a link farm on compromised WordPress sites strongly suggests malicious intent. The ML classifier and ClamAV detection further support this, flagging the PDF as malicious. The embedded JavaScript likely serves to execute malicious code or redirect the user, while the link farm aims to obscure the true destination or host malicious files.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 7

  • 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.
  • 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://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a599ed8fc59---surezivegexomawag.pdf In PDF document text
    • https://vmwarts.com/ecovic/file/39965315250.pdfIn PDF document text
    • https://bancodevida.com/bancodevida/admin/images/image/file/60553817174.pdfIn PDF document text
    • http://mlight.cz/archiv/file/26979634233.pdfIn PDF document text
    • https://la-klamm.org/userfiles/file/patiwagej.pdfIn PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f3c6b04519---41844008800.pdfIn PDF document text
    • https://konferencii.ru/js/ckfinder/userfiles/files/wotap.pdfIn PDF document text
    • https://istocdukkan.com/userfiles/files/15558574811.pdfIn PDF document text
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160826b7aeecfa---9209493651.pdfIn PDF document text
    • https://www.fifatravels.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082e6ca7281e---99579440327.pdfIn PDF document text
    • http://bigxra.com/uploadfile/file/2021051912531673499.pdfIn PDF document text
    • http://shadesvalleymounties1969.com/clients/868959/File/68399546160.pdfIn PDF document text
    • http://iphonedown.com/ckfinder/userfiles/files/13556948552.pdfIn PDF document text
    • http://creativeindustries.ru/uploads/userfiles/file/nemumiralivelanefijevok.pdfIn PDF document text
    • http://aaaexpressac.com/userfiles/file/bojoseji.pdfIn PDF document text
    • https://quickonboarding.com/wp-content/plugins/super-forms/uploads/php/files/b57f9d1fb88f01e37a2f6b82173c536f/31338087100.pdfIn PDF document text
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160b83aad7b146---55698986721.pdfIn PDF document text
    • https://sanmuabancongty.vn/images/content/files/diwonafus.pdfIn PDF document text
    • https://muzeumkonstancina.pl/attachments/file/2086159662.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160943510bb20a---vorazirisogisejuz.pdfIn PDF document text
    • http://jhferry.com/data/fckeditor/file///soluriragosemareriseg.pdfIn PDF document text
    • http://sotel-perm.ru/site/file/24777377679.pdfIn PDF document text
    • http://hoskinspugs.net/clients/40498/File/wivoweziwovu.pdfIn PDF document text
    • https://interior-mark.com/ckfinder/userfiles/files/mizorukin.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=icd+10+code+for+convulsionsPDF 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_off0000ef28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF28 18560 bytes
SHA-256: e32395462ea96e2618869d1fcfab6e41e87da8b2849426042ed22da1d28ab41c
font_01_sfnt_off00011fd6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FD6 10500 bytes
SHA-256: f7e3db789868ae68b9aced420410d9afb2a61107396ff23f56bcb53f4e04640c
font_02_sfnt_off000137df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x137DF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1