Malicious PDF — malware analysis report

Static analysis result for SHA-256 7da67d8c136ef357…

MALICIOUS

PDF

87.3 KB Created: 2021-09-06 01:23:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 7b4f61238fa9a6cc233b80bc51db65d3 SHA-1: 8e0d44bc769dbd3e168fdf983b24ff7ff8de29e3 SHA-256: 7da67d8c136ef3578cfab56902e18edf682e5dd7984113010aae8175f3f742f3
96 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to files hosted on compromised CMS upload directories, suggesting a link farm or distribution mechanism. The ML classifier strongly indicated maliciousness. While no scripts were extracted, the structure and URL patterns are indicative of SEO spam or a distribution point for further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://debsecond.net/UserFiles/File/74279005868.pdf In PDF document text
    • http://portalcom-b2b.es/img/user///file/_0633155001624768592.pdfIn PDF document text
    • http://valifyrepapillon.com/clients/6/68/68e1c6a84db99a04c21676ff826d6e37/File/defedumoduwemanebuse.pdfIn PDF document text
    • https://www.glasswindowequipment.com/wp-content/plugins/super-forms/uploads/php/files/1a20671a15ff704591038841ece90705/xaxusubufipozasujelugego.pdfIn PDF document text
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609989f639c40---18434029427.pdfIn PDF document text
    • http://pphjako.pl/userfiles/file/wabidemop.pdfIn PDF document text
    • https://churchosonline.com/wp-content/plugins/super-forms/uploads/php/files/736c59e69fbf60c424c027eaf390ee33/38925771480.pdfIn PDF document text
    • https://mednet.mk/public_html/upload/userfiles/file/88757453483.pdfIn PDF document text
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1608348bd773c5---98267841235.pdfIn PDF document text
    • http://wawa757.com/uploads/files/rokojak.pdfIn PDF document text
    • http://akademia-jedenastka.pl/zdjecia/fck/file/2555524242.pdfIn PDF document text
    • http://auxerretv.com/content/public/file/31089378596.pdfIn PDF document text
    • https://siam-royal-view.ru/data/files/wemek.pdfIn PDF document text
    • http://goldartline.ua/userfiles/file/84008527809.pdfIn PDF document text
    • https://italvaping.com/file/73253573148.pdfIn PDF document text
    • http://gewald.ru/content/Files/jomugebag.pdfIn PDF document text
    • http://cgpreceptor.com/ckfinder/userfiles/files/sivonemis.pdfIn PDF document text
    • https://moulindelarroque.com/userfiles/file/bosakapikivapovopubufo.pdfIn PDF document text
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b4d75bdf12b---29710790477.pdfIn PDF document text
    • http://delve-cr.com/uploads/70631917591.pdfIn PDF document text
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b81e3626f57---lerowisumaga.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=mild+hybrid+electric+vehicle+pdfPDF link annotation
    • http://zs.tom.ru/jsplugins/ckfinder/userfiles/files/99556710165.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_off0000ef3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF3D 10476 bytes
SHA-256: 9018a4c6553b621ce9555eb489136480b212a061357fc76152514c728f7e1448
font_01_sfnt_off000106eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106EB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011efd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EFD 18588 bytes
SHA-256: a02c532acce4257e8f401a6894cf9028b6046e1cb17cab75b16856ccc8ab7d13