Malicious PDF — malware analysis report

Static analysis result for SHA-256 fdb1664cfceb9230…

MALICIOUS

PDF

75.2 KB Created: 2021-07-18 03:41:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 20f44feb00ef01e761a3bb35970b9538 SHA-1: 788f015cdf9c36ff10c1d3c136796b3e96799ef2 SHA-256: fdb1664cfceb923085789d13cb4dac1f1e14320430413038275933d31b4847c1
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 phishing or trojan threat. It functions as a link farm, with numerous URLs pointing to compromised WordPress upload directories and disposable hosting domains, likely intended to lure users to malicious content. No scripts were extracted, and the document body was unreadable, but the heuristic firings strongly suggest a phishing or exploit delivery attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://netinflux.net/userfiles/file/piresuluwofalajugo.pdf In PDF document text
    • https://www.nexidia.it/wp-content/plugins/super-forms/uploads/php/files/8e3d49271ae195c8eee74e401fdb8c14/pojewupiga.pdfIn PDF document text
    • http://biancoacolori.it/userfiles/files/xojunok.pdfIn PDF document text
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d9f184ce28---tofovaketekiwaxoje.pdfIn PDF document text
    • https://www.americansummercamps.com/wp-content/plugins/formcraft/file-upload/server/content/files/160846709e8871---kuxexebekapukege.pdfIn PDF document text
    • http://pck.malopolska.pl/wp-content/plugins/super-forms/uploads/php/files/f1e074d3012885a4906c6da27bd38455/57855916930.pdfIn PDF document text
    • https://www.peeryhotel.com/wp-content/plugins/super-forms/uploads/php/files/94f00fca5c73875994a042405289efe5/davijetaw.pdfIn PDF document text
    • http://kolesnikov.pro/ckfinder/userfiles/files/loridosiwavabifepimosolof.pdfIn PDF document text
    • https://royal-art.pl/uploads/userfiles/files/wibibujubetil.pdfIn PDF document text
    • http://alternativefitness.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607257a8ea789---93424853801.pdfIn PDF document text
    • https://www.sehersirin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bb4bbb2236---23859079579.pdfIn PDF document text
    • http://clair-environnement.eu/catalogue_dynamique/file/7888831878.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/1609d3e9e71487---27904083001.pdfIn PDF document text
    • http://xn----7sbakn3aoflleitf3m6a.xn--p1ai/userfiles/file/27312266167.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160793c965577a---dewobuzazegisexafemif.pdfIn PDF document text
    • http://seigyobannkaigaikikaku.com/ckfinder/userfiles/files/fojoso.pdfIn PDF document text
    • https://ural-aiti.ru/admin/ckfinder/userfiles/files/zelowoxuluzox.pdfIn PDF document text
    • http://chamdure.com/DATA/files/40368035143.pdfIn PDF document text
    • http://millecolori.it/images/file/jubomoxoluk.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160a7316a17a76---dilutoxajugonotaxino.pdfIn PDF document text
    • https://velvetskin.pl/wp-content/plugins/super-forms/uploads/php/files/c8fce3533608f3788c3bbdbec1284c06/58396222613.pdfIn PDF document text
    • https://alnahamgroup.com/userfiles/file/4167025096.pdfIn PDF document text
    • http://ikkosushi.com/uploads/files/34000533612.pdfIn PDF document text
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/160824879f09bb---3899612635.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=fire+fireboy+and+watergirlPDF 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_off0000c536.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC536 16372 bytes
SHA-256: 0081011e9ecbae2b07380577d142fb89c1bcb32405bc0b1120ebeb011575fe12
font_01_sfnt_off0000ef58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF58 10676 bytes
SHA-256: e09f0c247d00d0deb1d3f6302f990379dd603ff850dfc721294bb6292b9994d3
font_02_sfnt_off000107c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107C4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1