Malicious PDF — malware analysis report

Static analysis result for SHA-256 ec8b1ff3d6b2bec9…

MALICIOUS

PDF

83.3 KB Created: 2021-09-16 00:06:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: c0c719d20f2d91ccb21cda381fb34afe SHA-1: 9385eb92e65ae71b681024688f1a3bdcea9f623e SHA-256: ec8b1ff3d6b2bec9e26fac1539c94dc684cc1ec2e56cea616dcec30e648a857b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of external links, many pointing to compromised WordPress sites and disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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 https://infrive.ru/uplcv?utm_term=baixar+aplicativo+foto+3x4+para+android PDF link annotation
    • http://besteva.com/upload/files/ketoduzepolab.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613be3cd44ead---fuwogofabubelawudutoko.pdfIn PDF document text
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/161315c084216b---lemetudisavuxa.pdfIn PDF document text
    • http://przystaneknida.pl/data/aktualnosci_imgs/file/59445180005.pdfIn PDF document text
    • http://karat-dobremiasto.pl/userfiles/file/88356141469.pdfIn PDF document text
    • http://www.agrosystem.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613560536617e---mowulematitavakitopupaze.pdfIn PDF document text
    • http://panda-es.tokyo/yamituki-n/uploads/files/xazodosuwatixufili.pdfIn PDF document text
    • http://urotunisia.com/uploads/FCK_files/file/75455160178.pdfIn PDF document text
    • http://mudrkanuch.sk/editor_uploads/system/files/97547426742.pdfIn PDF document text
    • http://yildizteknikelektrik.net/resimler/files/komodivolalezata.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/39912988256.pdfIn PDF document text
    • http://nationalherbo.com/userfiles/file/daropesedunasibukali.pdfIn PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614123b4297d5---piboxeruf.pdfIn PDF document text
    • https://lmbri.com/WYSIWYGImage/file/516872162.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132d92b0bdb9---sanubezitog.pdfIn PDF document text
    • http://yacpa.org/yacpafiles/file/52381382310.pdfIn PDF document text
    • http://cancunday.com/travela/img/files/64230992747.pdfIn PDF document text
    • https://shoppe.everybodyisnotdoingit.org/gift/userfiles/files/67416830642.pdfIn PDF document text
    • http://gestaocipa.com/public_html/Imagens/file/50127523013.pdfIn PDF document text
    • http://tindangnhadat.vn/upload/files/72530188228.pdfIn PDF document text
    • http://infinity8talents.com/userfiles/file/momemevag.pdfIn PDF document text
    • 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_off0000db0c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB0C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f31e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF31E 20000 bytes
SHA-256: 624f9555853439b9c004db77fb3503be5025ca4f2e2bbf8a4c358ea9860f087c
font_02_sfnt_off000124fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124FA 10784 bytes
SHA-256: 0dbec049b7d1ab320cdbcab2f74fef4189dbaff23a52f9790bfbdb6072388c2c