Malicious PDF — malware analysis report

Static analysis result for SHA-256 b00439d4ed052cb4…

MALICIOUS

PDF

88.2 KB Created: 2021-09-09 09:43:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 866604cde084d013c24a483a1ddea272 SHA-1: 906854b6f5fb8d690e29560aed948b5f44a01a7a SHA-256: b00439d4ed052cb4072e560603e62a3a8339f20d94d6cd043a2f516e0d208f09
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, with numerous URLs pointing to potentially compromised websites and disposable hosting. The presence of a 'download button' lure further suggests an attempt to trick the user into clicking these links, likely leading to further malware or phishing attempts.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://ringid.vn/ckfinder/userfiles/files/63767375742.pdf In PDF document text
    • http://aitrans.org/UploadFile/file/F1202109031426192440.pdfIn PDF document text
    • http://fthyhs.com/resource/docContentImg/file/2021-09-07/08fa60d104b818873dd9d92223bafb87.pdfIn PDF document text
    • https://webgirls-studio.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136b686d68df---vobumazavenele.pdfIn PDF document text
    • http://jlsxjy.com/right/UploadFile/file///2021090909025873499.pdfIn PDF document text
    • http://www.agenbenangbandung.net/file/ropofolivizo.pdfIn PDF document text
    • https://razredna-nastava.net/files/75606300273.pdfIn PDF document text
    • https://perkunasstudio.com/uploads/files/202109052349264968.pdfIn PDF document text
    • http://a-xian-coat.com/uploads/files/202109011359595139.pdfIn PDF document text
    • https://promise-land.com/upload/file/97679636754.pdfIn PDF document text
    • http://mueblesdepladur.es/1/userfiles/file/pemejalitozemuvitudilusu.pdfIn PDF document text
    • http://seatraderhk.com/userfiles/pimokurepifadi.pdfIn PDF document text
    • http://xn--b1agjlwjc3g.xn--p1ai/ckfinder/userfiles/files/25118021170.pdfIn PDF document text
    • https://www.syria-report.com/sites/all/libraries/ckfinder/userfiles/files/xixulibiranemawogol.pdfIn PDF document text
    • https://tomas-music.com/contents/files/87705552119.pdfIn PDF document text
    • http://tnslib.su/userfiles/files/26931252938.pdfIn PDF document text
    • https://h1t-urlaurora1-turbo.com/contents/files/98216851160.pdfIn PDF document text
    • http://tuecpa.com/file_media/file_image/file/84992608001.pdfIn PDF document text
    • https://www.physioaktivkramer.de/wp-content/plugins/formcraft/file-upload/server/content/files/1612effaeae285---zadoxawika.pdfIn PDF document text
    • https://journeypeople.cc/wp-content/plugins/super-forms/uploads/php/files/1f7deab4f1020d83426d8a1335a150a6/95057132160.pdfIn PDF document text
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/2k9a9n79enpsk8mbff1v8gg0l5/mizedofugurofaka.pdfIn PDF document text
    • http://ain.proximeo.com/ckfinder/userfiles/files/poretiguzajabaveme.pdfIn PDF document text
    • http://blackhorsesc.pl/userfiles/file/64861480048.pdfIn PDF document text
    • http://pro-customer.de/userfiles/file/52807277166.pdfIn PDF document text
    • http://vdtonline.vn/static/uploads/editor/files/21599558658.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=merekam+audio+internal+androidPDF 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_off0000f1b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1B3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000109ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109CA 10424 bytes
SHA-256: ba54b14efe80b01cb3b1ff9f46e8fc49d6a6b0e68faab0e8aecb863b8f0c8757
font_02_sfnt_off00012154.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12154 19088 bytes
SHA-256: de30dd11bf4f47f1834b2fd7b5765f2829c1a278b27b5dacc77ee9f7727281ed