Malicious PDF — malware analysis report

Static analysis result for SHA-256 a0f3e271d790a818…

MALICIOUS

PDF

75.6 KB Created: 2021-09-02 10:06:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: f89622bd9df72177500659cf5a6793cd SHA-1: a8fc7e688bfa31ce8892731196c034ceec2e9958 SHA-256: a0f3e271d790a8189829a1a51ac88146e2e177ad083927b3c66db21521639afa
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to compromised CMS upload directories and disposable domains, indicating a link farm designed to distribute malicious content or manipulate search engine results. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious intent. No scripts were extracted, but the extensive use of external links suggests a potential for further exploitation or redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • 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://allytemp.ru/uplcv?utm_term=wear+out+meaning+in+english PDF link annotation
    • http://aarogyamedico.com/userfiles/file/wekopemovulikupezanatuj.pdfIn PDF document text
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160ac9586e91b4---fivosagikidabenirikuner.pdfIn PDF document text
    • https://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/039e4fb41f69e7acd36cfd6e288d8d78/bulowitepudojokus.pdfIn PDF document text
    • http://maidnheaven.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dfa67e0144---29957561943.pdfIn PDF document text
    • https://motiwalainstitutes.org/userfiles/file/zazopor.pdfIn PDF document text
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dc2149b069d---digewi.pdfIn PDF document text
    • http://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094091a4bf68---xiwutaniw.pdfIn PDF document text
    • http://thementalhealthadvocates.org/files/userfiles/file/20531895230.pdfIn PDF document text
    • http://www.rkcomdesignservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071dc152be2b---54336241498.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/16082688a646ff---muvaselisamepubeviriweja.pdfIn PDF document text
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/m0r4lsafdckpo64fv07qmpav4t/foluponagaxifepejatadipus.pdfIn PDF document text
    • http://farashimirooz.com/files/dimima.pdfIn PDF document text
    • https://darkoyunpin.com/calisma2/files/uploads/38408829125.pdfIn PDF document text
    • https://adepotcustom.com/UploadFiles/file/20210525193551175.pdfIn PDF document text
    • https://bmw-zona.ru/uploads/file/44586198974.pdfIn PDF document text
    • http://fullcolorspandoeken.nl/userfiles/file/21369014658.pdfIn PDF document text
    • http://electriccityusa.com/images/fck_uploads/file/lijagufutanuva.pdfIn PDF document text
    • http://mariautonoleggiomarsala.it/userfiles/files/nemukuvuxeked.pdfIn PDF document text
    • https://interconformity.ro/images/file/31265928410.pdfIn PDF document text
    • https://leifs-auto.dk/images/file/zubogura.pdfIn PDF document text
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160bf90de846b5---78067645414.pdfIn PDF document text
    • http://helpibr.org/clients/f/fe/feaff840d005acecac0f151e8679c8db/File/pasatuzozumawazapub.pdfIn PDF document text
    • https://perfecthospital.org/FCKeditor/file/83715152058.pdfIn PDF document text
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608463fbe6d90---mirenulitazugosomiwabe.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_off0000c241.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC241 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000da53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA53 17848 bytes
SHA-256: 97e61169d7f4455d981a07c3bf8aef1f393c00292a7eb2818ef23487f76044a4
font_02_sfnt_off00010865.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10865 10648 bytes
SHA-256: a80a12f2f3c1d370fbab58b841952044b0beba04df557766cf6c00ee21c789b2