Malicious PDF — malware analysis report

Static analysis result for SHA-256 898382e45da7ec9c…

MALICIOUS

PDF

79.2 KB Created: 2021-08-08 13:49:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 692ce7555560dd2dd63c4ad02bb4b2f1 SHA-1: 7d4703c3ce7a6bcc384981977f483ec62a53f912 SHA-256: 898382e45da7ec9cdbc9f1e08b9d8282fe5703935396e754ffeb5a5c41b9e35b
156 Risk Score

Malware Insights

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

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to distribute or obscure malicious content. The embedded URLs, while some are marked benign, contribute to the overall pattern of redirecting users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

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.criteriainvest.com.br/wp-content/plugins/super-forms/uploads/php/files/bjl7gtc1oj1nq5af3sotvbbfpa/34959799690.pdf In PDF document text
    • http://www.iece.in/userfiles/file/bufezamul.pdfIn PDF document text
    • http://phuquytravel.com/nguyenvanlinh/files/74168672287.pdfIn PDF document text
    • http://gsemilia.it/userfiles/files/kexubekokomelawunokebo.pdfIn PDF document text
    • https://centrosteadycam.it/wp-content/plugins/super-forms/uploads/php/files/f9f037be4c5c2cabaff97dd9825c5d4c/bageredovekopilawaxuvok.pdfIn PDF document text
    • https://bearings.vn/images/ckeditor/files/jubejixifemojetozuf.pdfIn PDF document text
    • http://ux-school.ru/files/files/girasinanatuvumeguw.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c502f36dd40---firipeguvaxaluwewemiz.pdfIn PDF document text
    • https://master.plus/wp-content/plugins/super-forms/uploads/php/files/42fa3bcb4019e83085460b88aea1f546/gazojaduveneg.pdfIn PDF document text
    • https://www.scmsgroup.org/ckfinder/userfiles/files/misibexedavanatukatatonu.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610673b0ec399---66542841384.pdfIn PDF document text
    • https://ajwatravel.com/wheelmarine/userfiles/file/28585432319.pdfIn PDF document text
    • http://meadspool.com/clients/8/8e/8e46726fd42f39913d2349bbdb4e70c4/File/rezagozalubun.pdfIn PDF document text
    • https://www.areatransfers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160884fb334b56---pefodu.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/16080f315a4f55---demukeragekilemip.pdfIn PDF document text
    • http://prospekt-rostov.ru/ckfinder/userfiles/files/83315948185.pdfIn PDF document text
    • http://neodev.space/wp-content/plugins/formcraft/file-upload/server/content/files/1608f4278a93a3---84789170843.pdfIn PDF document text
    • https://qualitycountscleaning.com/wp-content/plugins/super-forms/uploads/php/files/c9efb5c99b40cb01864cdab715957c99/9105265654.pdfIn PDF document text
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610d9d5b5049a---90943047337.pdfIn PDF document text
    • http://spreewaldatelier.de/img/editor/file/65709184566.pdfIn PDF document text
    • http://altadirezione-consulting.it/userfiles/files/5747432166.pdfIn PDF document text
    • https://www.engltg.com/wp-content/plugins/super-forms/uploads/php/files/5fef04bb1a5a043a42cad8e76cb1f950/pisamikidadadegulewase.pdfIn PDF document text
    • http://hart-metale.pl/gimnazjum/userfiles/file/9172166327.pdfIn PDF document text
    • https://dgaspcsm.ro/ckfinder/userfiles/files/tefosikew.pdfIn PDF document text
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080d30ec7477---68675090744.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=political+philosophy+the+essential+texts+3rd+edition+pdf+freePDF 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_off0000d1a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1A4 11108 bytes
SHA-256: 7ec4c405a8093f4a8a65b380ca6ebc13327013e5157eeedb790892d601f5291e
font_01_sfnt_off0000eb99.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB99 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000103ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103AB 16320 bytes
SHA-256: e1257714c36fefa0dd607d75300dd4d717f28ace4ad2ad65aaf24c94beba9b47