Malicious PDF — malware analysis report

Static analysis result for SHA-256 28bd103faba1cd4a…

MALICIOUS

PDF

125.8 KB Created: 2021-07-06 04:20:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 8d0d82d8b72093c4dda97b86f5fd8251 SHA-1: d128027832b4d54718c6d975206c37db149de677 SHA-256: 28bd103faba1cd4ad7ee94596fbd9c90582fb1f30f95e1be9bb23b646538e314
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links pointing to compromised WordPress sites, which in turn host other PDF files. This structure suggests a link farm designed to distribute malicious content or lead users to phishing pages. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d19a18035bc---3410925595.pdf In PDF document text
    • https://sellerflows.com/wp-content/plugins/super-forms/uploads/php/files/a3a72d22df7866da5601f954690409b4/7996255220.pdfIn PDF document text
    • http://franklinbristerharveyfamily.com/clients/a/a8/a8910385c57dfddac3c6311e2bd1422e/File/51744926636.pdfIn PDF document text
    • https://thietbivesinhanhhuy.com/asset/files/90627756711.pdfIn PDF document text
    • http://diplomat2014.ru/ckfinder/userfiles/files/nosunovozokonejuv.pdfIn PDF document text
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608c8b15d2bc9---35913206085.pdfIn PDF document text
    • http://arablift.net/userfiles/file/34800898177.pdfIn PDF document text
    • https://banktapeunadana.com/tapeunadana/bank2/admin/userfiles/file/98843471846.pdfIn PDF document text
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/160ac2284e70f8---godiwatelolufofolata.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/sibetibagasoxulo.pdfIn PDF document text
    • https://watfordfairtrade.org/app/webroot/img/files/85423119311.pdfIn PDF document text
    • https://www.endthestigmacounselling.com/wp-content/plugins/super-forms/uploads/php/files/52csovke91rjb1bsphjammdmmv/43450957091.pdfIn PDF document text
    • http://imssp.by/data/images/fxeditor/file/vulon.pdfIn PDF document text
    • https://mikepromedia.com/wp-content/plugins/super-forms/uploads/php/files/8tojigi78l1tuvveqqsjusgv73/biwoxofegipixifuxezefosej.pdfIn PDF document text
    • http://perfectthesale.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b102c02ff6c---xikojoniliwifanexoxeniko.pdfIn PDF document text
    • http://rethabise.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160b2bab37ee6d---91824705360.pdfIn PDF document text
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/160802592517b0---basimuropubapuwijoridij.pdfIn PDF document text
    • http://www.suffaheducation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082478ba44c8---38333644004.pdfIn PDF document text
    • http://pavcargo.ru/wp-content/plugins/super-forms/uploads/php/files/6e433393282048cda46b77a33699650d/ponifadijopabej.pdfIn PDF document text
    • http://birons.net/wp-content/plugins/super-forms/uploads/php/files/b21f20a47519607d13d0fd6864f2608f/45941799872.pdfIn PDF document text
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/16af4872ffc22a9194a1c4e1c637532a/lexijufelaxogej.pdfIn PDF document text
    • https://www.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a52f9b70bf---mefoz.pdfIn PDF document text
    • http://iaestedresden.de/userfiles/file/18134656640.pdfIn PDF document text
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d36d2ac304---60248333216.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=ingredients+in+dunkin+donutsPDF 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_off00018b4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18B4E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001a365.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A365 10360 bytes
SHA-256: 816982131f033927160fecb1ff9c6ba851e43e8675dad74062d5825914b8d0bb
font_02_sfnt_off0001bab4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1BAB4 17964 bytes
SHA-256: 6e663e9068dc5114703ca8206df2689a3e9ea482e6f83f86c905022f9beb91ae