Malicious PDF — malware analysis report

Static analysis result for SHA-256 4399d719160d5ac4…

MALICIOUS

PDF

87.5 KB Created: 2021-06-28 23:28:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 50c3ba1657ef4cfa6a6a3c06e27fa3ae SHA-1: e7f1b114203634cefafc195a688cdad9e5878de5 SHA-256: 4399d719160d5ac46ad451ed4ae2e568cf205b673a97c41e47c38a33fcb95899
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous URLs pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to malicious content or phishing sites. The presence of multiple external URIs and link farms points towards a tactic of SEO poisoning or distributing further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://pebyte.com/wp-content/plugins/super-forms/uploads/php/files/5jut6rce0ehe813rq26a6tu2ot/17316336203.pdf In PDF document text
    • http://synthecinter.com/userfiles/files/ladar.pdfIn PDF document text
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160bba24540365---33942727292.pdfIn PDF document text
    • http://bmsorganica.com/userfiles/file/bokiworizoxeb.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9612ed6ebb---dokogonugo.pdfIn PDF document text
    • http://antifftech.com/uploadfile/file///2021051420464438.pdfIn PDF document text
    • https://digireg.gr/upload/99929256692.pdfIn PDF document text
    • https://menu2uplus.com/images/file/83198578881.pdfIn PDF document text
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/7df88a5b48e9cc833518b6d7fcd24181/lazaf.pdfIn PDF document text
    • https://extremetour74.ru/wp-content/plugins/super-forms/uploads/php/files/65c85449cf64ca92ae5a57d9787be634/57978106017.pdfIn PDF document text
    • http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/0u7u0vq518dfehvv0m01e36ad3/migegorezufagolope.pdfIn PDF document text
    • https://whiteelephant.co.in/wp-content/plugins/super-forms/uploads/php/files/42cdee103295c660c3a33cc6d1ea820a/wunavipamukolamixum.pdfIn PDF document text
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/16099e27cf02c4---51272446072.pdfIn PDF document text
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160857582ac8f4---40858738204.pdfIn PDF document text
    • http://soft-pro.hr/upload/datoteke/dijuwijuvolonosulo.pdfIn PDF document text
    • https://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160c4a81616ec7---dimugadetafux.pdfIn PDF document text
    • https://imagebeaute.fr/userfiles/file/41383066332.pdfIn PDF document text
    • http://tunglamgarden.com/images/fck/file/momimosagejovitida.pdfIn PDF document text
    • http://sllight.ru/design/img/upload/file/41325144013.pdfIn PDF document text
    • http://langeline.com/ckeditor/upload/files/bowawugavojag.pdfIn PDF document text
    • http://www.gaviprintpack.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c36b68bd8f3---73983044595.pdfIn PDF document text
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/160a17b1ccc0c2---vovusugerupoteb.pdfIn PDF document text
    • http://www.peopleoftheheath.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cb3b6bdf4fc---wodan.pdfIn PDF document text
    • http://aaexpansionjoint.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab63b3d0deb---8568305865.pdfIn PDF document text
    • http://www.veronicaneal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/160bdee7b9c535---84732478544.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=equation+of+the+volume+of+a+spherePDF 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_off0000f00f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF00F 17880 bytes
SHA-256: 609f84f6745199fa4013e10015f2fc3397d8f61fc28d03268b5bfdc52e9fe655
font_01_sfnt_off00011f82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F82 10916 bytes
SHA-256: b464af03cce87b5932a5f9d8abc56be2cd1eb4886d98f821294007cf8205e7ba
font_02_sfnt_off00013897.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13897 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1