Malicious PDF — malware analysis report

Static analysis result for SHA-256 fc759e3b8729d9cc…

MALICIOUS

PDF

70.2 KB Created: 2021-09-28 22:01:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: d9d1af0e41b1b2c222f3229a891ee100 SHA-1: 863ccf43d65082942711573cda46ec176afb40b6 SHA-256: fc759e3b8729d9cc79b26f10ff660d13d5fe033593c73b8607fb725484d9485d
156 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded URLs, many of which point to compromised CMS uploads and disposable hosting, indicating a link farm designed for redirection. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to lure users to malicious sites or download further payloads. No scripts were extracted, and the document body was unreadable, so the primary attack vector appears to be the exploitation of user trust through deceptive links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://dh-cell.com/ckfinder/userfiles/files/genojaxakiduxuze.pdf In PDF document text
    • https://lanegarrett.net/userfiles/file/sumis.pdfIn PDF document text
    • http://daiquangsico.com/img_duhoc/files/viremepali.pdfIn PDF document text
    • https://stl-log.com/htdocs/cljr/data/files/jogemomurekelinavasopu.pdfIn PDF document text
    • http://sxsasa.org/images_fck/file/1632040708.pdfIn PDF document text
    • https://harpethvalleypto.org/wp-content/plugins/super-forms/uploads/php/files/9dc0cbf28ba7522bcd16a18d90f8e989/53318377655.pdfIn PDF document text
    • http://sfipl.in/userfiles/file/35167329237.pdfIn PDF document text
    • http://westfallassociates.com/documents/file/86726509436.pdfIn PDF document text
    • http://constantemail.com/userfiles/file/163068826794385036615.pdfIn PDF document text
    • http://optimaglobal.net/ckupload/files/42093777256.pdfIn PDF document text
    • https://gujaratisamajparis.org/upload/files/70916617360.pdfIn PDF document text
    • https://imagebeaute.fr/userfiles/file/17855637289.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/161453636e0b9a---ropamupubopumi.pdfIn PDF document text
    • https://almuhja.ps/ckfinder/userfiles/files/kizej.pdfIn PDF document text
    • http://michaelwilliamslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/texaduloju.pdfIn PDF document text
    • http://xedaptheduc.net/app/webroot/uploads/files/takovizadanopopebu.pdfIn PDF document text
    • https://principesgs.com/userfiles/file/53711810218.pdfIn PDF document text
    • https://guruamardaspublicschool.com/userfiles/files/74768635572.pdfIn PDF document text
    • https://macleanpinesdrivingschool.com.au/wp-content/plugins/super-forms/uploads/php/files/be49de9b5fbc463e27b25c169058abf0/56333939369.pdfIn PDF document text
    • https://philly.drinkpoint.com/uploads/files/7581039750.pdfIn PDF document text
    • http://www.village-gaulois.org/gestion/ckfinder/userfiles/files/45837298011.pdfIn PDF document text
    • http://lignumweb.com/site/webroot/uploads/files/89780065952.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=midnight+club+ppsspp+android+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_off0000aef8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAEF8 17116 bytes
SHA-256: 3ef7e72a59c4ca860098862a410f47d50cd2679e5e3a19440e9482654ce73d61
font_01_sfnt_off0000da51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA51 10980 bytes
SHA-256: b181056442876680547ca9e3a272bbeebcc6bd324f8d372146529658cccb82a2
font_02_sfnt_off0000f358.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF358 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1