Malicious PDF — malware analysis report

Static analysis result for SHA-256 02023073a8380db3…

MALICIOUS

PDF

74.3 KB Created: 2021-09-02 08:28:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: d8c967a37c6f66cc725df1d3febba0a4 SHA-1: e4c9770e87987d33906560146b46c396c8c7d8bb SHA-256: 02023073a8380db33d02489d8d3130c7fd01d7a24d408f8bd824ad8f1ce45a15
96 Risk Score

Malware Insights

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

The PDF file was flagged by an ML classifier as malicious. Static analysis revealed it functions as a link farm, containing numerous URLs pointing to compromised websites and disposable hosting. These links likely serve to manipulate search engine results or distribute further malicious content, aligning with common phishing and SEO spam tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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 http://caphegiabao.com/upload/fck/file/datut.pdf In PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610680354ac99---puwafujawijugekazowut.pdfIn PDF document text
    • http://tykhestudiodesigns.com/clients/7/73/7311521ca682816632878891c231d107/File/65683092414.pdfIn PDF document text
    • http://www.hptindia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f706332d79---88695137354.pdfIn PDF document text
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/0c231366a430d0f5580e8a94c634fb9d/fafujetutasekobowetojob.pdfIn PDF document text
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a915f1c5859---niwozumep.pdfIn PDF document text
    • https://majubesar.com/contents//files/tababar.pdfIn PDF document text
    • http://sl-light.ru/design/img/upload/file/rajawexi.pdfIn PDF document text
    • https://stancijanegrin.com/UserFiles/files/11765052913.pdfIn PDF document text
    • http://shinserviceodi.ru/wp-content/plugins/super-forms/uploads/php/files/3d92f0564a8c707356248ca396ec53f3/lizajugurifijexinokifa.pdfIn PDF document text
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607731c25d851---72664256554.pdfIn PDF document text
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/38l40tm0u5ha919i26tnb0192k/73842752430.pdfIn PDF document text
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609109b44e55a---xemegenugesukawukas.pdfIn PDF document text
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc290553be---56191508770.pdfIn PDF document text
    • https://cobrawire.com/userfiles/files/nifefumefojamudafikuzos.pdfIn PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/160905666b7321---veropudifevirogalot.pdfIn PDF document text
    • https://kompaspt1.com/contents//files/19025233183.pdfIn PDF document text
    • https://callhfelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b1e8e4a71d---muvedexat.pdfIn PDF document text
    • https://tonwen.org/userfiles/file/20742740237.pdfIn PDF document text
    • http://micruts.org/userfiles/file/43823171173.pdfIn PDF document text
    • https://ardiinerkh.mn/uploads/userfiles/files/zesukifejufu.pdfIn PDF document text
    • http://louisefarmersmith.com/admin/ckeditor/ckfinder/userfiles/files/85401451306.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=psp+games+direct+downloadPDF 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_off0000c097.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC097 15844 bytes
SHA-256: d12b0a99258b85f1e51f93bd2316c96a153681b69c09fb807e4eaa8e1334768f
font_01_sfnt_off0000e921.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE921 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010138.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10138 10944 bytes
SHA-256: 58e3dec1987b7d9f9deea5879b7126f0a57c27bc4b1063b6e1cb26a84939a8a8