Malicious PDF — malware analysis report

Static analysis result for SHA-256 ae9d9ec5d7b102a4…

MALICIOUS

PDF

89.3 KB Created: 2021-09-05 14:49:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 181a5b60da43172e9a59a6b09028499e SHA-1: aac24c551eaf8c1fa96b7adb5255fda337b3f321 SHA-256: ae9d9ec5d7b102a44333723f495c1097c7dc12218dffc238afa9970810441914
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised or disposable hosting. The ML classifier strongly indicated maliciousness, and the heuristic firings confirm the presence of a link farm designed to redirect users to external sites. The primary purpose appears to be traffic distribution or potentially leading users to malicious content hosted on these external sites.

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 http://wcsps.com.tw/ckfinder/userfiles/files/85608639629.pdf In PDF document text
    • http://galantemontagnana.it/ckfinder/userfiles/files/40638225766.pdfIn PDF document text
    • https://gw21.ch/uploads/userfiles/file/18640051480.pdfIn PDF document text
    • https://open-call.fr/uploaded/files/19048249005.pdfIn PDF document text
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fe8d422b57---80447874197.pdfIn PDF document text
    • https://kindliving.org/wp-content/plugins/super-forms/uploads/php/files/tmp/baxevulafir.pdfIn PDF document text
    • https://expresstestingatl.com/wp-content/plugins/super-forms/uploads/php/files/2b943df80c7c9ff7aab68390751c686d/nowozojupeluga.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a284e3d985c---76558708255.pdfIn PDF document text
    • http://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4d83145e1c---luzon.pdfIn PDF document text
    • https://proektasis.gr/admin/spaw2/uploads/files/difewewolifutabasejuse.pdfIn PDF document text
    • https://dtcprojects.com.au/wp-content/plugins/super-forms/uploads/php/files/m9a83e9c86bbtgv66eirbf3p62/fiperuzuwisukozag.pdfIn PDF document text
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/46b61dc097c2e2b0ab7d443045117e67/58846431089.pdfIn PDF document text
    • https://sharmtocairo.com/userfiles/files/90770947902.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/a343035e2a3a0520c8f29afe0185259b/97417793930.pdfIn PDF document text
    • https://www.azulejositurry.com/wp-content/plugins/super-forms/uploads/php/files/f34cfeks540ehs1k87l6jpjt42/87782096388.pdfIn PDF document text
    • http://parquessolaresdenavarra.com/userfiles/files/wuzopitepeg.pdfIn PDF document text
    • http://glastergroup.ru/userfiles/file/48884629652.pdfIn PDF document text
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091610389f94---25674226082.pdfIn PDF document text
    • http://n-production.com/upload/fckeditor/file/jasosadovazizofur.pdfIn PDF document text
    • http://kstarsmall.net/userfiles/file///83856238417.pdfIn PDF document text
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1611afea4568ab---tadiwowaluzaleforeweje.pdfIn PDF document text
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c2cd14f66e---tubotelavenoxuzora.pdfIn PDF document text
    • http://auchli-appenzeller.ch/userfiles/files/joresexut.pdfIn PDF document text
    • https://arte-salon.ru/upload_picture/gexesuwedoluw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=ieee+papers+on+artificial+intelligence+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_off0000f6da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6DA 18372 bytes
SHA-256: 65bd455962176d75521f8f103e0bd8ca5af490f48e8d5308bf4929f3430209d8
font_01_sfnt_off00012663.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12663 10744 bytes
SHA-256: 5fd3fc60c5d8f5f677f1742b13a4b7819411d05781bd05b3bae827091c5743b5
font_02_sfnt_off00013f00.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F00 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1