Malicious PDF — malware analysis report

Static analysis result for SHA-256 5d155ea6f804fa15…

MALICIOUS

PDF

74.8 KB Created: 2021-09-08 16:22:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: cdc01324fea7ec7218eca76d9d45f1b9 SHA-1: 83617e0ca5a6d712e8c0ce94461ecea65f379802 SHA-256: 5d155ea6f804fa15f8a9aa9094769457387f9be71b9e25f9c5911a1a7f11cb0c
204 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a link farm pointing to multiple domains, some of which are identified as compromised CMS upload storage. The embedded JavaScript likely facilitates the download and execution of a second-stage payload. The presence of a ClamAV detection for 'Pdf.Phishing.Trojan' and ML classifier flagging further supports its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • LOLBin token sequence in document text high SE_LOLBIN_RUN_COMMAND
    Extracted document text contains a Windows script/execution tool name (PowerShell, mshta, cmd, rundll32, regsvr32, …) within 220 characters of a dangerous flag, command verb, or URL. This is a visible 'run this' instruction in HTML/PDF/RTF lure bodies, or — in macro-laden Office files — the macro's own string-pool entries appearing adjacent in extracted text.
  • 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 http://charmingcurls.se/upload/file/kuwezawonafob.pdf In PDF document text
    • http://investin-khj.ir/ckfinder/userfiles/files/tatisaliwinewabapiki.pdfIn PDF document text
    • https://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16133bf156f92e---19236467879.pdfIn PDF document text
    • https://laps.pl/userfiles/file/92596938897.pdfIn PDF document text
    • http://bhavalaya.org/ckfinder/userfiles/files/75251153892.pdfIn PDF document text
    • https://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/797d1e63527e484953147a86171e1503/nifuroxefiwetigejenefifag.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136bb26d1500---putofev.pdfIn PDF document text
    • https://seo-methodes.com/userfiles/file/31316184441.pdfIn PDF document text
    • http://hoteldanang.com/uploads/images/files/92739781606.pdfIn PDF document text
    • https://www.studiorosaliabusco.it/ckfinder/userfiles/files/voboxedojujazigoravu.pdfIn PDF document text
    • https://dursunguney.com/userfiles/files/29245817142.pdfIn PDF document text
    • https://espritgt.com/userfiles/file/27554769058.pdfIn PDF document text
    • http://domusanna.it/userfiles/files/befidetemoxuka.pdfIn PDF document text
    • http://spamsmsgiare.com/media/ftp/file/nemowekikozo.pdfIn PDF document text
    • http://steclotildehorton.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613634e331f61---2016721809.pdfIn PDF document text
    • http://coeb.eu/userfiles/files/69052727492.pdfIn PDF document text
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/a97efa0e33c6eb5f2efef9d43ad4580d/95093782665.pdfIn PDF document text
    • http://okna-kurska.ru/page_edit/_samples/userfiles/files/40980343814.pdfIn PDF document text
    • http://fullx.net/files/gozolarezexuxujobi.pdfIn PDF document text
    • http://global-poseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/161377e20294c8---41467863683.pdfIn PDF document text
    • https://ateliersmq.com/pevron/www/img/file/57604760850.pdfIn PDF document text
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/161349c8e95682---vibisemeleretekasekuroros.pdfIn PDF document text
    • http://ptsound.com/plugins/ckfinder/userfiles/files/kugeditonudajadekunodezu.pdfIn PDF document text
    • http://tecs4.com/intranet/ckfinder/userfiles/files/mogalewiwomamipelu.pdfIn PDF document text
    • http://nanchang.chinatupai.com/web/js/ckfinder/userfiles/files/48564357759.pdfIn PDF document text
    • http://bestorkate.com/uploads/ckeditor/files/bifekejesesunekawitadeg.pdfIn PDF document text
    • http://investin-khj.iIn macro / runtime command snippet
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=hermetismo+livros+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_off0000c389.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC389 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dba0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBA0 10448 bytes
SHA-256: bd5053d151c5126808f5524f2aed2931bbcc69bd65ed043dc69ccd675908da72
font_02_sfnt_off0000f350.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF350 16356 bytes
SHA-256: f3596a594ed18ae31ded0dea3547d113e95f9b7ddbcdb76db9382c8647a8979a