Malicious PDF — malware analysis report

Static analysis result for SHA-256 1d553c1418670d50…

MALICIOUS

PDF

106.1 KB Created: 2021-09-07 16:02:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 03c53a7ad2c4581e766bd01b84167003 SHA-1: fe863099ba67aa9055c61f711811348fbffc2591 SHA-256: 1d553c1418670d50af262b1065336bc209569447c62c2b8e320886a984b6945c
156 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 potentially compromised websites or are structured as link farms. Heuristics indicate a 'PDF link farm' and a 'compromised CMS upload link', suggesting the document's primary purpose is to redirect users to external, potentially malicious content. The ML classifier and ClamAV detection strongly support a malicious classification.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://seashoresilverlabradors.com/clients/4/48/482fd9669fb3260065120a60ccac5e48/File/4615385313.pdf In PDF document text
    • http://c-six.it/userfiles/files/rovuxokivove.pdfIn PDF document text
    • http://someteme.com/archivos/_20210705190023.pdfIn PDF document text
    • http://soupworld.de/upload/file/79912746460.pdfIn PDF document text
    • https://baobihungphu.com/media/ftp/file/fekakalekaxe.pdfIn PDF document text
    • https://masterpieces-mallorca.com/wp-content/plugins/super-forms/uploads/php/files/ac1167a1dc6a8cb4370e18880a2c6ee7/27735376780.pdfIn PDF document text
    • http://helloslow.com/data/userfiles/files/75222369169.pdfIn PDF document text
    • http://biurod9.pl/public/userfiles/file/bijoxojupo.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ef36a809bd---sifebovik.pdfIn PDF document text
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16083a91a3bb0e---1293843365.pdfIn PDF document text
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16109bcb2a8e3f---29008004562.pdfIn PDF document text
    • https://franciscovalles.comtraining.cl/userfiles/files/43259202034.pdfIn PDF document text
    • http://linpus.com/app/webroot/userfiles/files/72798003240.pdfIn PDF document text
    • http://novosib-sport.ru/ckfinder/userfiles/files/nidodolijumo.pdfIn PDF document text
    • http://aqcons.vn/upload/files/23493422005.pdfIn PDF document text
    • https://artsketch.ru/wp-content/plugins/super-forms/uploads/php/files/2e9b4eb8c56c7fa01484d6c5decb4fc3/16260574605.pdfIn PDF document text
    • https://greyquotient.com/wp-content/plugins/super-forms/uploads/php/files/c66039f7299ab625c80e473628ed98d1/93451077059.pdfIn PDF document text
    • http://americanewbie.com/userfiles/file/vizemituwuzamogasinujibe.pdfIn PDF document text
    • https://zazilha.com.mx/wp-content/plugins/super-forms/uploads/php/files/e8c0a83029cdce8aede04c8c08b20e37/45296143645.pdfIn PDF document text
    • http://sh-ruiyangcpa.com/userfiles/file/2021-7///2021728122463489.pdfIn PDF document text
    • https://condicionamentofisico.com/arquivos/file/49792595487.pdfIn PDF document text
    • http://d4sontario.com/clients/e/ed/ed023a0734c265ca673a92d1d81de675/File/xutovipodazuxemojemi.pdfIn PDF document text
    • https://churchosonline.com/wp-content/plugins/super-forms/uploads/php/files/bc49fbbd13673e4ac896cb59f14f5ed3/makibi.pdfIn PDF document text
    • http://gewald.ru/content/Files/filijalamus.pdfIn PDF document text
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610e6ece5ba3a---82216992644.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=livros+literatura+infantil+em+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_off0001321b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1321B 10784 bytes
SHA-256: 1d7f2e29bd945a789f0bb9fc3f22c1029454a8b10402b18e484fcefbabd44c51
font_01_sfnt_off00014af3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14AF3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00016305.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16305 21980 bytes
SHA-256: 48cf2d19d3a591bc9a98a1e20878ab59a4d6e181812e29c8b1f34731ad92a881