Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8ecc52513a01363…

MALICIOUS

PDF

83.9 KB Created: 2021-08-14 09:50:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: f81f1fccbec70876cf9cbc891532fe89 SHA-1: 5abfc9687e9b44c348be2ecf8aa87d74d39e65de SHA-256: b8ecc52513a013633164fa16a3898cce2580bff0f549a8c6078152540f65aac8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to other PDF files hosted on compromised WordPress sites. The presence of multiple external URIs and link farm heuristics suggests a phishing or malware distribution campaign. No scripts were extracted, but the PDF structure itself is used to facilitate the redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/9ad5mk59oiktmbkoa066vvmfu4/vagunujunerimos.pdf In PDF document text
    • https://www.frankreich-ferien.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1609e98e4d2940---tabatudig.pdfIn PDF document text
    • https://noukos.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1607249eea0a0f---22454047166.pdfIn PDF document text
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/299dfe8f9178790cd4b07298403af488/buganepomoded.pdfIn PDF document text
    • http://scandirent-new.ru/uploads/assets/file/nukubebisome.pdfIn PDF document text
    • https://kassa-evotor.ru/wp-content/plugins/super-forms/uploads/php/files/689js10n8ama98q9s18n6vrid9/42780601861.pdfIn PDF document text
    • http://lirealestatelitigator.com/wp-content/plugins/super-forms/uploads/php/files/5dd48709bcff9f6f19663c05a6555a78/16189902276.pdfIn PDF document text
    • http://montaze.org/democms/userfiles/file/45991349338.pdfIn PDF document text
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089e7ed90a93---joxawevomirizupafotufaw.pdfIn PDF document text
    • http://vasvaripalmuzeum.hu/upload/file/lopewikawubetepusotuxim.pdfIn PDF document text
    • https://spencershaulageltd.co.uk/wp-content/plugins/super-forms/uploads/php/files/27c57731508778f266e2e76fa6fdb509/84678517638.pdfIn PDF document text
    • http://asfalon.com/__files/file/40884501375.pdfIn PDF document text
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160e23db9ca526---nemopoz.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3f08c8ee8e---68736459557.pdfIn PDF document text
    • https://drmarlenebothma.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16071efdc5e3a0---23880671738.pdfIn PDF document text
    • http://domeinbeverdonk.be/assets/files/file/73388481934.pdfIn PDF document text
    • https://www.helpforbusymums.com/wp-content/plugins/super-forms/uploads/php/files/ee2dd95064b6f43cb6823b490c978324/gadawututo.pdfIn PDF document text
    • http://businessplan-capalpha.eu/mbp/upload/images/images/upload/ckfinder/vabixo.pdfIn PDF document text
    • http://sspvjd.com/FileData/ckfinder/files/20210721_D8E57423B2E666CC.pdfIn PDF document text
    • https://legacyltg.com/wp-content/plugins/super-forms/uploads/php/files/bd6737a26adc823e00d81a3cad812066/pusalavedelam.pdfIn PDF document text
    • http://davcpundri.com/css/file/96529096983.pdfIn PDF document text
    • https://www.ideaklinikizmir.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075581360e83---47719288535.pdfIn PDF document text
    • https://blagoustroystvo24.ru/ckfinder/userfiles/files/rajuxitonetiguzivapuforan.pdfIn PDF document text
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e87a13cb13---24012682344.pdfIn PDF document text
    • http://sochi-vitrazhi.ru/ckfinder/userfiles/files/54920656146.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=sumas+de+dos+cifras+llevando+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_off0000e100.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE100 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f912.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF912 18112 bytes
SHA-256: 43c01639c18e8ec32b1afc16606879cd2885a3c4b244915a0967d9d9117a1c8e
font_02_sfnt_off00012701.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12701 10924 bytes
SHA-256: 0a6492c4652fdedd93e39b50eca2c733bf5c44fb4df43b5f5c20cb22e037f3d2