Malicious PDF — malware analysis report

Static analysis result for SHA-256 83b1036b7d5b1fce…

MALICIOUS

PDF

85.1 KB Created: 2021-07-04 03:23:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: bcf24601253d0e17e806baaef6acce65 SHA-1: 3241f9c2ccf7cc796547e5cf28ed499c747dc57d SHA-256: 83b1036b7d5b1fce3d49dcfa85b599c1b55cdcf9344347427a82f05b7aa25f45
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs that point to various domains, many of which appear to be compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of these links and the overall structure strongly indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://crewmak.ru/uplcv?utm_term=too+good+to+go PDF link annotation
    • http://travisreunion.com/clients/1/1d/1d9c560ef9ee6310b862f4c9d288d7bd/File/41895449593.pdfIn PDF document text
    • http://xn--9w3b11kh5l.com/ckupload/files/soxivufetifuzigegatuz.pdfIn PDF document text
    • https://szabobuszberles.hu/files/files/dowusamufevexugopubida.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160784eb3afa37---safunalezevira.pdfIn PDF document text
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a234714833e---52780602740.pdfIn PDF document text
    • https://alllegaltask.com/wp-content/plugins/super-forms/uploads/php/files/kvps3cu273vviofm4a26pmuua0/zujijasuxotepixo.pdfIn PDF document text
    • https://xo-sound.ru/userfiles/file/66698218879.pdfIn PDF document text
    • https://123natura.com/stockages/files/71881388359.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/qegesap11hgt9g13crtvau9n24/42870931994.pdfIn PDF document text
    • https://dezsredstvompx.ru/wp-content/plugins/super-forms/uploads/php/files/90e7da9a6cdf5c61d101e7b82d5fffcc/43698313595.pdfIn PDF document text
    • https://completecollegestrategies.com/wp-content/plugins/super-forms/uploads/php/files/296079bb03c20098c5502730f9793e2d/nuzekawaladofokaradat.pdfIn PDF document text
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/9dqspv9m4nd79i4t1vv2db5sa3/9115380204.pdfIn PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160a78055839d9---mawimamisiz.pdfIn PDF document text
    • http://klefmarken.se/upload/file/sakejukuwelotifu.pdfIn PDF document text
    • https://creativesilhouettes.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160c25f4d3514e---8465266953.pdfIn PDF document text
    • http://www.emailposte.com/pictures/tajiwemam.pdfIn PDF document text
    • https://tkpmission.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608ba93795adf---fevixomibamalebotex.pdfIn PDF document text
    • https://www.myjamaicais.com/wp-content/plugins/super-forms/uploads/php/files/63c9f31a75847bcec4d9379ced08be3b/wezuxox.pdfIn PDF document text
    • https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/kq22a4fo10g1pts9tjags0i6qj/gifezusikuxufiduwagapi.pdfIn PDF document text
    • https://www.beewellrx.com/wp-content/plugins/super-forms/uploads/php/files/tmp/33294842561.pdfIn PDF document text
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16070e1ff5095a---89759415996.pdfIn PDF document text
    • https://dedywiredja.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078badb2ae9e---9782796360.pdfIn PDF document text
    • http://matstravel.ru/userfiles/file/kikipumubakajinazesevesog.pdfIn PDF document text
    • 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_off0000eeef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEEF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010705.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10705 9580 bytes
SHA-256: 9f8b864e520f405d7a5dbd30218d3eb89336d402515cdbe7a9b675e8a0a39b48
font_02_sfnt_off00011b88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B88 16992 bytes
SHA-256: da7430322ca60c1547f2d86ef1149f30efe86b8fdea8fb9c1da2e80ffa3149ed