Malicious PDF — malware analysis report

Static analysis result for SHA-256 22a12b89e94a4817…

MALICIOUS

PDF

71.3 KB Created: 2021-06-24 05:13:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 3de26bfd8f57e308613393c9a2011967 SHA-1: 430922310bc49e121438a89a08aefa2ec7556479 SHA-256: 22a12b89e94a48178297406aa0d1073bb792734dc2b789205d1d764bccf90e3b
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 upload directories, indicating a link farm or redirection strategy. ClamAV detected this file as 'Pdf.Phishing.Trojan', and ML classifiers also flagged it as malicious. The document body is heavily obfuscated and contains metadata suggesting it was generated by wkhtmltopdf, but the primary malicious activity appears to be the distribution of links to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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 http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608775d913837---71202697599.pdf In PDF document text
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c060b292cea---9959281515.pdfIn PDF document text
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a333cdd8a1d---nupekikifesiligitolijuwu.pdfIn PDF document text
    • http://grodgolf.com/clients/f/fd/fd83fa7079552abb47853a85229f74c1/File/7735244817.pdfIn PDF document text
    • https://benjamindreyer.com/wp-content/plugins/super-forms/uploads/php/files/a117bdf4120bf0df1d6a49afbdf6f902/rujajamepapodagafe.pdfIn PDF document text
    • http://gramercygrand.ru/files/file/kagusazojig.pdfIn PDF document text
    • https://e-lightingcontrols.com/wp-content/plugins/super-forms/uploads/php/files/a771fcf050cdc648a5437797eefcd3af/36185193545.pdfIn PDF document text
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/16071fd8cd4a4d---wekatuxopaladuzibojemun.pdfIn PDF document text
    • http://dossalas.com/wp-content/plugins/super-forms/uploads/php/files/a1cfc2204319f94743e908797e759114/67011536990.pdfIn PDF document text
    • http://hotechike.com/files/files/konavow.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e269ab7a2d---kuketabexega.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/16090550069b7c---6422017303.pdfIn PDF document text
    • http://cipetbhopal.com/webimg/files/47552347864.pdfIn PDF document text
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609dafd71aed3---woragewiwomulufuzekuzim.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=saltwater+reef+store+near+mePDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dbea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBEA 5108 bytes
SHA-256: d9ff40a4b4f4060714d09b0be05b69a4ec6208a8d2d73ed26589cf344f176a01
font_01_sfnt_off0000ed45.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED45 10412 bytes
SHA-256: 74ff868bd6f3304493b0b273b0b6a4f2b02b88ad34edd82b8bf9aa0f5ced8e27