Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8369c1fb611226e…

MALICIOUS

PDF

81.9 KB Created: 2021-09-24 07:47:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 5b9316b0a5475a314529e3dfb9b45cce SHA-1: 4f222426093e5b666228d40384ae74e551fbdd76 SHA-256: b8369c1fb611226e5b6cca3f1dc5ab014924496729eacfbe4e2a7992af489364
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. The presence of numerous embedded URLs, many pointing to disposable domains and structured as a link farm, suggests a phishing or malware distribution campaign. Although no scripts were explicitly extracted, the PDF structure and embedded links are indicative of techniques used to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://odnoklassniki-files.ru/images/uploads/files/tadazajunonavelaxof.pdf In PDF document text
    • https://used-machinetools.ro/app/webroot/files/userfiles/files/wajovefi.pdfIn PDF document text
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140f039cdf27---46909457898.pdfIn PDF document text
    • http://elite-nails.pl/Upload/file/72873002661.pdfIn PDF document text
    • http://baloneacessorios.com/_upload/file///35033077822.pdfIn PDF document text
    • https://vietucmould.com/img-vietuc/files/60566481553.pdfIn PDF document text
    • http://psychologkmalinowska.pl/ckfinder/userfiles/files/94194453438.pdfIn PDF document text
    • http://architettoseneca.com/userfiles/files/xomufotojajidodibejeza.pdfIn PDF document text
    • http://thaimassageboy.com/ckfinder/userfiles/files/56999495057.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/47265097795.pdfIn PDF document text
    • http://dylogistics.com/userData/board/file/puvovusi.pdfIn PDF document text
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613503f6a2bd7---29411730168.pdfIn PDF document text
    • http://urgentcarepb.com/userfiles/file/10307778622.pdfIn PDF document text
    • http://websteravelandscaping.com/editorData/file/48844695527.pdfIn PDF document text
    • https://adian.eus/files/galeria/files/58426488854.pdfIn PDF document text
    • http://goldendazzle.com/upload/quangtri/files/35159834152.pdfIn PDF document text
    • http://tidomusica.com/uploads/files/202109060107158612.pdfIn PDF document text
    • http://blessingsngo.in/userfiles/files/78722911738.pdfIn PDF document text
    • http://sushistoryus.com/uploads/files/rivepumodizitote.pdfIn PDF document text
    • http://kaymccarthy.com/immagini/file/banetiwixebisovanuji.pdfIn PDF document text
    • https://vanphongphamhienluong.com/upload/files/dafoxaresafotulugalo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=younger+pilot+script+pdfPDF 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_off0000dcdb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCDB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f4f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4F2 10716 bytes
SHA-256: 9b22f10286dcddddbd29e253d0353cc0c82f369b363e1e5e1950f44da604ac96
font_02_sfnt_off00010d72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D72 17160 bytes
SHA-256: a3abc2d94e06ba93e60c371eb7646cc4007b190b6a212ea11e60dfb4f8bf6a80