Malicious PDF — malware analysis report

Static analysis result for SHA-256 d8685e9b84d70803…

MALICIOUS

PDF

88.3 KB Created: 2021-09-04 08:22:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 1165f7231a92849698a38d30d9be798a SHA-1: 52b4cfda19e713e37acf9f7c9804537cfa70fae0 SHA-256: d8685e9b84d70803d0564f6ddc6e0da60952364c2bb964adeb048969bc4ed7da
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to various websites, many of which appear to be compromised WordPress installations. The ML classifier and ClamAV detection strongly indicate malicious intent. The document's structure suggests it's designed as a link farm to distribute traffic to these potentially malicious or compromised sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 https://www.finestkindcharter.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3dadfa7ccb---89132181612.pdf In PDF document text
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/7fef6081973e18a57452eea8d5ff7a6b/vejebumawetedevijadanagen.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096a7f6f29c4---74997191907.pdfIn PDF document text
    • http://leinerpakgelatine.com/survey/userfiles/files/36668046125.pdfIn PDF document text
    • https://www.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ec372564b7---puramatubogaxovavux.pdfIn PDF document text
    • http://wumag.pl/userfiles/file/56404963587.pdfIn PDF document text
    • https://funkydrop.shop/wp-content/plugins/super-forms/uploads/php/files/8315a71de3db766e1b65989aad7411f9/devuzedule.pdfIn PDF document text
    • http://ehoron21.mn/uploads/files/72904834149.pdfIn PDF document text
    • http://libertyquad72.fr/userfiles/file/wigojaxez.pdfIn PDF document text
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160b358b0787c7---xasitemazisipumeripolul.pdfIn PDF document text
    • http://www.bluewhaleline.com/image/upload/File/70176967545.pdfIn PDF document text
    • http://etre-belle.su/images/file/gazalarofokonomifu.pdfIn PDF document text
    • https://envida-nieuws.nl/bsb_website/upload_fck/file/fixom.pdfIn PDF document text
    • https://stpetejazz.com/wp-content/plugins/super-forms/uploads/php/files/n1rkiggvfioqf8p56hgknqd2ce/5037503421.pdfIn PDF document text
    • http://poslovniimenik.net/firme_data/files/69938789758.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160afb25e3de2f---76693111653.pdfIn PDF document text
    • https://amalighting.com/wp-content/plugins/super-forms/uploads/php/files/e0069a46b26a5998fd59a7b1230123e1/vemimekusakujakupo.pdfIn PDF document text
    • http://naturabliskociebie.pl/userfiles/file/48088421202.pdfIn PDF document text
    • https://pearproperties.in/userfiles/file/72199318812.pdfIn PDF document text
    • http://otohondamientay.com/upload/files/15710082901.pdfIn PDF document text
    • http://liddellgaryfamily.com/clients/863293/File/sasan.pdfIn PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608513d0b8913---57873724407.pdfIn PDF document text
    • http://mirandatutoringcentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b873dd8932a---24147248738.pdfIn PDF document text
    • https://cupanghitam.com/contents//files/78244100316.pdfIn PDF document text
    • http://beloezoloto.ru/userfiles/file/jawokamonanulosizisu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=reuven+feuerstein+livros+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_off0000e6f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6F9 10540 bytes
SHA-256: 1341ec4d217a855ac899fb965a60b2ab62bd55cb85e7ce981dc8dde1751ec625
font_01_sfnt_off0000ff20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF20 23920 bytes
SHA-256: 1d0afbe14a6ba9f391fa62dff48cb9ba399b514aa054d2b0f3f6a50cc7c05efd
font_02_sfnt_off00013b4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B4F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1