Malicious PDF — malware analysis report

Static analysis result for SHA-256 75a4f97a96f34215…

MALICIOUS

PDF

69.3 KB Created: 2021-09-18 23:43:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: cfbce64ba7b6e7884329951ff39f938f SHA-1: d2df0034a265ba67956c28192a0687873f3253db SHA-256: 75a4f97a96f34215768f4c6ade4e419ce593ca3a6f29e2520186f3e89a05f83a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The 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 lure users to malicious sites. The PDF structure itself is simple, with no executable scripts, but the embedded URLs are the primary attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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 https://www.sevgiliyevideo.net/wp-content/plugins/formcraft/file-upload/server/content/files/161353acaaf15c---fikijogesusiwes.pdf In PDF document text
    • https://brawlcall.jordanadams.com/ckfinder/userfiles/files/fekipojosoworasujoma.pdfIn PDF document text
    • http://circolosilverblufitnessclub.eu/userfiles/files/zurulamu.pdfIn PDF document text
    • http://ozdesignhouse.com/app/webroot/uploads/files/73471065157.pdfIn PDF document text
    • http://mobilahomedesign.com/userfiles/files/57643008925.pdfIn PDF document text
    • http://mardeestilos.es/fotos/file/ribijigafososi.pdfIn PDF document text
    • https://huaku3c.tw/uploads/files/202109101824238423.pdfIn PDF document text
    • https://hostsolutions.ro/app/webroot/files/userfiles/files/36375169551.pdfIn PDF document text
    • http://thietbibepnhahang.net/media/files/29983735396.pdfIn PDF document text
    • http://sun-apartments.pl/data/pages/senuz.pdfIn PDF document text
    • http://seibyou-koujien.com/files/files/togamip.pdfIn PDF document text
    • http://bbdecontra.com/userfiles/files/52667045827.pdfIn PDF document text
    • https://doitsolutions.co/wp-content/plugins/super-forms/uploads/php/files/ad2354d7203331e489e0419001d2867d/66137709978.pdfIn PDF document text
    • http://archidaldegan.eu/userfiles/files/89079741888.pdfIn PDF document text
    • http://lotusburbank.com/uploads/files/1243561525.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/16137e5a714cba---wilisibexodejowovugijirit.pdfIn PDF document text
    • https://maftplayer.net/calisma2/files/uploads/ropetobagigo.pdfIn PDF document text
    • http://sushrutproctology.org/ckfinder/userfiles/files/tiladikabi.pdfIn PDF document text
    • https://0922.sproname.com/files/userfiles/files/80177486686.pdfIn PDF document text
    • http://intproplaw.com/admin/uploads/file/rebelutolop.pdfIn PDF document text
    • http://sb-78.ru/files/file/netige.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=video+editor+inshot+app+downloadPDF 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_off0000b0c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB0C7 15308 bytes
SHA-256: a5ca9f4c95f5f875481037767d1ed71f0521a811b74fe864338c252677b18efc
font_01_sfnt_off0000d7ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7CA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000efe1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFE1 10544 bytes
SHA-256: 5dcfc6e53ed9326029922bf33534e6739dae25ff18838c78b12708c12003856c