Malicious PDF — malware analysis report

Static analysis result for SHA-256 3c83ce93f86c7f35…

MALICIOUS

PDF

81.4 KB Created: 2021-09-03 15:06:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: f44d2ab3583a03c2188aa3d4323fc6fb SHA-1: bf18c5f0e4035d8748b0fb878078e386329cfebf SHA-256: 3c83ce93f86c7f35eef8002b8aef344210231d99c0a4f60a6beb95136d6003a9
164 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment

The sample is identified as malicious by ML classifiers and ClamAV, with high confidence. It contains embedded JavaScript, which is often used to execute malicious actions within PDFs. The presence of a link farm pointing to multiple distinct hosts, some of which are hosted on compromised CMS uploads, suggests an attempt to obscure the final destination and potentially distribute further malware or conduct phishing. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports the idea that this PDF is part of a campaign to drive traffic to potentially malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://web-sila.ru/wp-content/plugins/super-forms/uploads/php/files/fd54aab8e44d0305cc70e580a4cee3b3/winasujumumuwo.pdf In PDF document text
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/160e2beb7375e8---vonezepisogerixinib.pdfIn PDF document text
    • http://belean.pl/userfiles/file/wagikunisepa.pdfIn PDF document text
    • https://52fantasies.com/home/holly/public_html/ckfinder/userfiles/files/debufisuzamiliwegod.pdfIn PDF document text
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/c13ab3144672dee8e0bed18879a6ae31/23859867550.pdfIn PDF document text
    • http://mkconline.com/landmark/ckfinder/userfiles/files/33386768887.pdfIn PDF document text
    • https://securitydm.com/slicice/file/remezavopedod.pdfIn PDF document text
    • https://sinarwaja.com/account/files/19955353370.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b764a075394---77389195736.pdfIn PDF document text
    • https://kimtuong.vn/isc/public/files/fckupload/file/jipodukalesem.pdfIn PDF document text
    • https://alcoolassistance-creuse.net/www/site/js/ckfinder/userfiles/files/47202879880.pdfIn PDF document text
    • https://vieclamxaydung24h.com/upload/files/3474965044.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a512ac23f20---dazevaxibudivujapatotiku.pdfIn PDF document text
    • http://soflocops.org/clients/83264/File/16416229025.pdfIn PDF document text
    • http://project-st.ru/userfiles/file/kobuxuvogefutiwa.pdfIn PDF document text
    • http://bidwoodmachine.com/d/files/wivugupewetepejilererarud.pdfIn PDF document text
    • http://predit.ru/admin/ckfinder/userfiles/files/41419075339.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/160869b6217fc4---67399630453.pdfIn PDF document text
    • http://krikrik.ru/uploads/ckfinder/files/dusipelekexi.pdfIn PDF document text
    • https://cremyco.com/app/webroot/docs/file/sujotafepudizitejitomod.pdfIn PDF document text
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9a7124943f---riwonexunadajivaz.pdfIn PDF document text
    • http://pinturasoltra.com/images/slider/files/vewafuropinorikusomaxob.pdfIn PDF document text
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1610a0d9b80a59---motapejelog.pdfIn PDF document text
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609e070d65d8d---17531097949.pdfIn PDF document text
    • https://mls.lighting/wp-content/plugins/super-forms/uploads/php/files/d9872305534a0007a114b5e7dc69399b/wolowemijomidolazagag.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=cctv+camera+lens+types+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_off0000d9e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9E1 10780 bytes
SHA-256: 1c3bd0224429b18beae92ce621c97c29a9b228f04ec28b0afa88896cf602473b
font_01_sfnt_off0000f2bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2BF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010ad1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AD1 17584 bytes
SHA-256: 7614186dc789aaa8d89800346069cd58c43c5797c65bf0804527c0558c0b2af7

Open this report in the interactive analyzer, or submit your own file for analysis.