Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4a366331b8ef2bb…

MALICIOUS

PDF

77.2 KB Created: 2021-09-07 13:46:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: de978f554d7d93b9322bca3f479fcee1 SHA-1: 8c9100e74723f1c2c56b91015ea60b06df6518fe SHA-256: d4a366331b8ef2bb8ffcf2eafef488f10331ed8a68777702eb4a98afa52a068c
96 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs pointing to various websites, many of which appear to be compromised CMS uploads or disposable hosting. The ML classifier strongly indicates maliciousness, and the structure suggests a link farm designed to redirect users. The presence of external URIs and link farms points towards a phishing or SEO manipulation tactic.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://smidgel.ru/uplcv?utm_term=vademecum+de+medicamentos+mexico+pdf PDF link annotation
    • http://dga.gr/ILC/img/file/49621070536.pdfIn PDF document text
    • http://mgtofubbq.com/uploads/files/52339631152.pdfIn PDF document text
    • https://www.fmworks.com.tr/wp-content/plugins/super-forms/uploads/php/files/p0158e5lutj3oa2k2o5bv0uks5/38665813339.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608e82b7c0e6b---jatizarelinugalox.pdfIn PDF document text
    • https://actsonics.com/uploads/files/202109011333541461.pdfIn PDF document text
    • http://dekoblickfang.de/userfiles/file/kipivix.pdfIn PDF document text
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/1608dc6b0b70b8---selagafisofixa.pdfIn PDF document text
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/f6e6fd1328b66c353927653def74e32f/dotitifewidagatoluj.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/bsuqc94jmmmgdgf78faqnpllt2/tatemaz.pdfIn PDF document text
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cf2d92ab9fc---panekizew.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160837f093fc61---mozafeduditobufijiw.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/851d35237c26a7a7f19253787f9125c9/xupegegowekimot.pdfIn PDF document text
    • http://npas.ru/pic/file/famunokerozojisivipupokof.pdfIn PDF document text
    • http://www.alcera.ca/userfiles/file/47189275687.pdfIn PDF document text
    • https://extremetour74.ru/wp-content/plugins/super-forms/uploads/php/files/db540577071e3247e991c908624a519f/dolexowanowawosu.pdfIn PDF document text
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16092ccf1a0d26---41541828651.pdfIn PDF document text
    • https://ce-mi.pl/uploads/userfiles/files/guvimatizubafel.pdfIn PDF document text
    • http://pratiklinik.com/img/userfiles/files/54488953552.pdfIn PDF document text
    • http://studiosantomauro.it/userfiles/files/79896541725.pdfIn PDF document text
    • http://roosprommenschenckelfoundation.nl/userfiles/file/96261802562.pdfIn PDF document text
    • https://gencatakan.com/upload/file/51981179401.pdfIn PDF document text
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a045c004b87---terusologutafozutu.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_off0000c606.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC606 18440 bytes
SHA-256: e95f87bc4ef89ff34be5d16048096c3e95c53a2d75f6fefaadd7abddefa37f98
font_01_sfnt_off0000f4b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4B8 10804 bytes
SHA-256: d56bd140b123e88ae211f56e1d29997f4dcdf4846452b544ceedad976cc03d6f
font_02_sfnt_off00010da2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DA2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1