Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b0f5a5bc62b6b5f…

MALICIOUS

PDF

80.8 KB Created: 2021-09-04 13:38:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 1365c15c58de22d274693aff6eb964ac SHA-1: 6d62e74ed78fdaa63710060ce6f0c150a7127ddc SHA-256: 5b0f5a5bc62b6b5f75ae7f9f142ae875086394f1120177378054181485769bf4
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or are part of a link farm on disposable hosting. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution through these links. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://progfin.pl/userfiles/file/wibusewum.pdf In PDF document text
    • http://www.mkkdigital.pt/wp-content/plugins/formcraft/file-upload/server/content/files/160a3e578d0797---xedelibej.pdfIn PDF document text
    • https://phoenixknights.co.uk/wp-content/plugins/super-forms/uploads/php/files/497cdf406f6e862dd702857e20c6444c/kazofosaberazo.pdfIn PDF document text
    • http://spearsyounglegacy.com/clients/b/b2/b2c23f164518415ec8f3c1c8d0af542d/File/28563479022.pdfIn PDF document text
    • https://estidevelopers.com/wp-content/plugins/super-forms/uploads/php/files/04dff256063f098158fd4cefd791e4bd/73026522720.pdfIn PDF document text
    • http://infinity-pro.ru/userfiles/file/zoderolulalujago.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1606cfef5cb757---29557300048.pdfIn PDF document text
    • http://www.pianoszimmermann.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a208028f120---89800728362.pdfIn PDF document text
    • https://diversified-nj.com/wp-content/plugins/super-forms/uploads/php/files/3739b3e4b8df50115cf5c131a2817544/414970529.pdfIn PDF document text
    • https://harpethvalleyhealth.com/wp-content/plugins/super-forms/uploads/php/files/e62dbc6b68d6b20c3166d1baa14638f5/xotasufizotu.pdfIn PDF document text
    • https://nazragame.com/calisma2/files/uploads/64874101834.pdfIn PDF document text
    • http://toonesk.com/upload/88937736069.pdfIn PDF document text
    • http://tangiahoang.com/skinkorea/Images_upload/files/52537806106.pdfIn PDF document text
    • https://al-farh-iq.com/upload/userfiles/file/66578599107.pdfIn PDF document text
    • http://short-story.ru/upload/file/tumabopodevajepukon.pdfIn PDF document text
    • https://selispin.com/calisma2/files/uploads/zukevesam.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/86ad9f8b601ef7f056b40e934d7e8ef1/76925330753.pdfIn PDF document text
    • http://tsrmvolontari.it/userfiles/files/kulojiwufizugifomemot.pdfIn PDF document text
    • http://xn--80aadcnaeutgftohcogh8i8dsc.xn--p1ai/pict/file/76198221069.pdfIn PDF document text
    • http://otevrel.eu/ckfinder/userfiles/files/kutaxisijajireliwomusal.pdfIn PDF document text
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/16098c270936da---78134737371.pdfIn PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/16073ee3774ec0---66004774077.pdfIn PDF document text
    • http://noithatlekhanh.com/Images_upload/files/97469394865.pdfIn PDF document text
    • https://empylean.com/wp-content/plugins/super-forms/uploads/php/files/j2lc3s383opjubitnciplea10s/27784798243.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=apics+supply+chain+management+fundamentals+pdfPDF 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_off0000d876.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD876 11040 bytes
SHA-256: 965f5456db6d51fecfd03141ff01ac3498e43ff2d9d18ed04c2cafca65657578
font_01_sfnt_off0000f1da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1DA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000109ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109EC 16800 bytes
SHA-256: b7dfd6c56ec3293813224802caec624a71f4710c38c39abfbd3912b31dc5f7e5