Malicious PDF — malware analysis report

Static analysis result for SHA-256 52454ea6a39c2dff…

MALICIOUS

PDF

76.9 KB Created: 2021-10-04 00:49:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 5841cf0ce1018428b0ff8a156750b842 SHA-1: 1e67fadf96d61079b0d32fff7344d8874061adf7 SHA-256: 52454ea6a39c2dff0228f2604355ad4483d85dd8a9a9349cd773aaa924e6d432
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, pointing to numerous URLs hosted on various domains, some of which are associated with compromised CMS uploads or disposable hosting. The primary purpose appears to be directing users to external sites, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://philabc.ru/uplcv?utm_term=death+note+eng+subs PDF link annotation
    • http://cn-junsheng.com/upload/file///20219201281444.pdfIn PDF document text
    • https://excore.hu/ckfinder/userfiles/files/77785797059.pdfIn PDF document text
    • https://lifesmart.ro/ckfinder/userfiles/files/70731601171.pdfIn PDF document text
    • http://hqshop24.com/userfiles/file/zavepuliziwob.pdfIn PDF document text
    • http://miwon.com.vn/app/webroot/uploads/files/dadimozipodegidudogasina.pdfIn PDF document text
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16151f12fd921d---65267013665.pdfIn PDF document text
    • http://ahjygjg.com/upload_fck/file/2021-9-11/20210911075416647953.pdfIn PDF document text
    • https://hagakure.by/upload/editor/files/97940107089.pdfIn PDF document text
    • http://cokhibaosang.com/media/ftp/file/5903855677.pdfIn PDF document text
    • https://mtmnetwork.net/uploadEditor/files/96246889017.pdfIn PDF document text
    • https://mysilo.com/upload/ckfinder/files/guwojaxiz.pdfIn PDF document text
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/1613f1214ab8cb---gokal.pdfIn PDF document text
    • https://pontus-sd.eu/uploads/file/6600290607.pdfIn PDF document text
    • http://yuhao-tech.com/userfiles/file/lekowaduboj.pdfIn PDF document text
    • http://xz-brand.com/ckfinder/userfiles/files/74598256146.pdfIn PDF document text
    • http://sunnyten.net/userData/board/file/69714291381.pdfIn PDF document text
    • http://silarperu.com/UserFiles/file/83877133708.pdfIn PDF document text
    • http://essiac.cz/UserFiles/file/12990185126.pdfIn PDF document text
    • http://daearesort.com/FileData/ckfinder/files/20210927_0A06BC1DE900CE11.pdfIn PDF document text
    • http://semihkerpiccilervesupersound.com/upload/file/18674444890.pdfIn PDF document text
    • http://utcsp.rustyramone.com/uploads/files/lovakafodelar.pdfIn PDF document text
    • https://bostaninsaat.com/image/files/68283055095.pdfIn PDF document text
    • https://dezsredstvompx.ru/wp-content/plugins/super-forms/uploads/php/files/f153bdde9ee73587a0a902286d1875c7/27272764825.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_off0000bd2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD2C 21800 bytes
SHA-256: e4bafc506b30bf2719fe6151ba7233e82c502369c4c857b2e354b99b17c8496f
font_01_sfnt_off0000f533.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF533 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010d4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D4A 10388 bytes
SHA-256: fa72881d8ff5522451179eb2be7a8c2b8d07116bef2afa9e0fdd46f6c34d7378