Malicious PDF — malware analysis report

Static analysis result for SHA-256 293441b2c3f0c9de…

MALICIOUS

PDF

69.2 KB Created: 2021-10-02 23:28:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: d5053a95f50c924caf4df3807e74261c SHA-1: 8f938da642e010d5f405c96361be1203a6dd8173 SHA-256: 293441b2c3f0c9de8fc389d6d29cb965e08673075dcb33640703edbaf153e897
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to external sites, many of which are hosted on compromised or disposable domains, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery via these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://krisoc.ru/uplcv?utm_term=use+of+figurative+language+in+poetry PDF link annotation
    • http://integrotech.com/zdjecia/file/83621717229.pdfIn PDF document text
    • http://cnpair.com/userfiles/file/12994724413.pdfIn PDF document text
    • http://bijverhoeven.nl/uploads/files/wavowopimodejunozapaliz.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1614e743601b16---nugepimivav.pdfIn PDF document text
    • https://repetitorebi.ge/userfiles/files/5625769417.pdfIn PDF document text
    • http://emekyesiltepe.net/images_upload/files/91853841756.pdfIn PDF document text
    • http://revistaspontan.ro/assets/ckfinder/core/connector/php/uploads/files/80519291613.pdfIn PDF document text
    • http://luberoff.com/userfiles/file/vozowowogamur.pdfIn PDF document text
    • https://mb-classic-service.de/userfiles/file/nemegex.pdfIn PDF document text
    • http://xn--12cxa2boh7cd6g7anex5omh.com/ckfinder/images/files/ziriwekapotidi.pdfIn PDF document text
    • http://isystemlab.com/admin/ckfinder/userfiles/files/37579692948.pdfIn PDF document text
    • https://valve-toho.com/userfiles/file/46973534232.pdfIn PDF document text
    • http://trunglam.vn/uploads/userfiles/file/limiretijixidotigaduto.pdfIn PDF document text
    • http://01host.ru/userfiles/files/61424133638.pdfIn PDF document text
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/1614f65e421b3b---65131524079.pdfIn PDF document text
    • http://sky1981.com/asset/uploads/files/kuxutenetewitegivapegojaf.pdfIn PDF document text
    • https://anapobolivia.org/userfiles/file/mukawuvavekuwedideruvup.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1614ddbce30859---6531111122.pdfIn PDF document text
    • http://cn-junsheng.com/upload/file///202191622219022.pdfIn PDF document text
    • http://wimborst-ceramics.nl/ckeditor/ckfinder/userfiles/files/kinaxodanujegiwamuk.pdfIn PDF document text
    • http://kd-council.com/upfile/files/20066967067.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/1614caef010b5d---muturogoxokemigetebajare.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_off0000b06d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB06D 10820 bytes
SHA-256: d85157097be93831492d37b84a13e463598bdccc67eff31f237b4a44b8362d9f
font_01_sfnt_off0000c992.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC992 14872 bytes
SHA-256: 4e29aba5ff36c985e62cc8fe9f8ee24e9baa6851bb474d7d3ef33dde90830492
font_02_sfnt_off0000ef11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF11 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1