Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf0af90c13145c12…

MALICIOUS

PDF

87.3 KB Created: 2021-07-02 17:48:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: d31e4ac05eb1653d668150ee9a8bcdf1 SHA-1: 083c362b164973fece4746203ae428a5c34106a7 SHA-256: cf0af90c13145c12fb7c9d272482154b553755891cbd6995a102904999ce9776
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1055.001 Process Injection

The PDF contains a link farm pointing to multiple distinct hosts, many of which appear to be compromised WordPress installations used for hosting PDF files. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The embedded URLs suggest an attempt to lure users to these compromised sites, potentially for further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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 http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dbb8d823696---xelexivizigixikukaraboku.pdf In PDF document text
    • http://danguykhoidoanhnghiephp.vn/Upload/files/1571971292.pdfIn PDF document text
    • https://inncredel.com/uploads/80524638274.pdfIn PDF document text
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/re50plakgb8943ibik7v0ssuo5/3056959876.pdfIn PDF document text
    • http://vodnik48.ru/content/file/21709774460.pdfIn PDF document text
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606f091d1c327---xutudoputagowofabisepuxa.pdfIn PDF document text
    • http://goodwill.pl/userfiles/file/bepobibunisop.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/b60a835afa2e98d6d9e74f96ac5493ad/bilijisipudimikali.pdfIn PDF document text
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607279c530030---36002250232.pdfIn PDF document text
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/3bac5c11190d7c54440ca3bed14fd744/fusolixenazofulerisarago.pdfIn PDF document text
    • http://hasanmasat.com/ckfinder/userfiles/files/76643302791.pdfIn PDF document text
    • https://psfund.org/public/uploads/files/cms_files/41021643534.pdfIn PDF document text
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16080612fae33d---74755331126.pdfIn PDF document text
    • https://astoriareiki.com/wp-content/plugins/super-forms/uploads/php/files/533f6c3deb1270c45c65a4a56bc1c0f8/kupudipofajusuwuvafofa.pdfIn PDF document text
    • http://amajyuku.com/files/files/velun.pdfIn PDF document text
    • http://thevisionkharj.com/userfiles/files/fesuwizatulazuga.pdfIn PDF document text
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/160a2f727ad801---famarabosiruno.pdfIn PDF document text
    • https://clubelsendero.com/img_pag/file/45800469983.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/160841089b08a0---8399069535.pdfIn PDF document text
    • http://www.redactordecontenidos.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160ae126360f8d---22146091677.pdfIn PDF document text
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/160742d4c8b918---35923034745.pdfIn PDF document text
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0d97626c90---vasasas.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=ccna+introduction+to+networks+skills+assessmentPDF 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_off0000ecf5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECF5 10840 bytes
SHA-256: 7370eb2c7a063ee7f30ab46c4990f138bc017882566805138fcbf197c73df3d3
font_01_sfnt_off00010619.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10619 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011e2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E2B 18740 bytes
SHA-256: 2509bb3d13aed4bdbccb841a977c86bef46ac08e945878df9fdcaff76087c7f4