Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b35bb45619b9eaf…

MALICIOUS

PDF

86.6 KB Created: 2021-09-01 01:21:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-18
MD5: a136e4d23fb44b4c9b67c1eb082601a6 SHA-1: 27bc7310aa3f32ac54f9c1b8db1466e406b3a3fd SHA-256: 7b35bb45619b9eaf9ae3478537698fa8a2c304c920ed14e2db6a0e0cc638f23f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many pointing to compromised WordPress sites and disposable hosting, suggesting it's part of a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate 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 0.9912

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://krisoc.ru/uplcv?utm_term=minecraft+1.8+hacked+clients PDF link annotation
    • http://xz-brand.com/ckfinder/userfiles/files/17718762400.pdfIn PDF document text
    • https://asharfilalkulfi.com/ckfinder/userfiles/files/powetajepusuke.pdfIn PDF document text
    • http://musicpark-live.de/userfiles/file/xojoj.pdfIn PDF document text
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/p1pti6hdos7mki55le96jdoh80/49545938859.pdfIn PDF document text
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c100bc6808d---minuxojezagirafofenitapaj.pdfIn PDF document text
    • http://www.mkkdigital.pt/wp-content/plugins/formcraft/file-upload/server/content/files/16091a095b3177---vetekejumotikusuroxef.pdfIn PDF document text
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/160ac5eae2f571---fipesiwagawaj.pdfIn PDF document text
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/vchcemjsuos389q1e18vedsrr0/73638374736.pdfIn PDF document text
    • http://josephfellerlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/98065307382.pdfIn PDF document text
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c41465065f1---57894680179.pdfIn PDF document text
    • http://studioboscono.it/userfiles/files/nagipiveboralomowanojurup.pdfIn PDF document text
    • http://ahzycw.com/upload_fck/file/2021-8-8/20210808091641818874.pdfIn PDF document text
    • http://werkkledingverkoop.nl/images/docman/files/39114544615.pdfIn PDF document text
    • http://www.ambredore.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c1c1528c93---67282023481.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/11ce17f3e79710944b8461c5aa8ff90a/168120892.pdfIn PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/160cf3b012aa58---wesewopedapirutavetanuki.pdfIn PDF document text
    • https://alebusph.centralcms.cloud/galeria/files/73885255084.pdfIn PDF document text
    • http://dedanskecasinoer.dk/userfiles/file/boxadijapub.pdfIn PDF document text
    • http://lawrence-spruill.com/clients/42275/File/32453176514.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/1606c73c41a0f1---gesubagofubog.pdfIn PDF document text
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/1609f0018b9a8e---modetixavedakode.pdfIn PDF document text
    • http://nguyenphat.com/public/default/ckeditor/files/69233539527.pdfIn PDF document text
    • https://www.emma-solutions.de/wp-content/plugins/formcraft/file-upload/server/content/files/16085101dd8014---72357344895.pdfIn PDF document text
    • https://betonwerkendejonge.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160bade83920c6---risezujulataxewiwu.pdfIn PDF document text
    • http://pvsystexperts.com/wp-content/plugins/super-forms/uploads/php/files/qvi70dcdpb37oodavmjcgkj8r2/62872437251.pdfIn PDF document text
    • http://sumnerclassof1976.com/clients/4/49/49b54eafcc86ae0c30eb104ab8b91c7c/File/97349105307.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_off0000ed59.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED59 18072 bytes
SHA-256: 5ac9919edba2b243846d2406d59374e4c28dfe327d0dce8e1b2a694a677b2072
font_01_sfnt_off00011c6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C6A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013481.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13481 10864 bytes
SHA-256: c98200bbce3789344e89514c53d270b413180b8aa2186b620a1dee66298ec26f