Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c65b8d1d87363f0…

MALICIOUS

PDF

85.9 KB Created: 2021-08-22 02:58:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d4ad9ae6d4f941be14671f13658e1bc2 SHA-1: 7b18c912a6e1662d699ed217895cb7382d8bab10 SHA-256: 8c65b8d1d87363f08eead42796f6078053efbbc7be6cc13ddbfae2a8bab99493
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress sites, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The file's structure and embedded links align with techniques used to host malicious content on compromised infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb737befc9b---tutoza.pdf
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/1608b1a924cae3---72843724110.pdf
    • https://www.marvistasales.com/wp-content/plugins/super-forms/uploads/php/files/8e1d7d562c9e36ea1e668cc9c6cdbf18/13031307913.pdf
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160895d49043fb---11939848920.pdf
    • https://penzion-palice.cz/content/79614916990.pdf
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d8ff0c00de---gemagefi.pdf
    • http://karmand24.ir/basefile/ehotel724ir/files/11000732076.pdf
    • https://www.alignerco.ca/wp-content/plugins/super-forms/uploads/php/files/6183cbf54087f250492989fe514a2f5c/98847655130.pdf
    • http://jiangsutravel.kr/userfiles/files/20210621_060215.pdf
    • http://anhbanglaw.com/userfiles/file/99271033796.pdf
    • https://harmony-lazienka.pl/Upload/file/99042844083.pdf
    • https://imagebuzz.net/ckfinder/userfiles/files/saromeniduwajetisazek.pdf
    • http://bigband-ulm.de/userfiles/files/37887720350.pdf
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160952d2fd174d---safizarozumemegox.pdf
    • http://dnepropress.net/files/file/rafodofetilo.pdf
    • http://canadanur.com/resimler/files/dipusorebumu.pdf
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160719d83d002c---51799459450.pdf
    • https://traicaygiasi.com/Images_upload/files/kerugutuxilomatezefute.pdf
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/16108b22f1d020---difaxup.pdf
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5346e94d83---92281392396.pdf
    • http://jinohair.com/upload/files/59761169861.pdf
    • https://brincandoeaprendendo.com/fotosempresa//files/gufomurofugevuk.pdf
    • http://aquamedia.cn/ckfinder/userfiles/files/53897177964.pdf
    • https://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/ec73028c4c49ba0eb14c0c2551871a82/14383820946.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=como+sumar+fracciones+con+diferente+denominador+con+mcm
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e780.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE780 16792 bytes
font_01_sfnt_off0000ff92.bin
aca4f02fb63d717db3b30fd932b2cc7db24e9c0ad51f97f46a26006b706a2617
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF92 18316 bytes
font_02_sfnt_off00012d53.bin
1ea44f081c560a37bef7a1d347f038801b1a2aa9d3c8585fdc2f9205f09bda59
pdf-font-stream PDF embedded font (sfnt) at offset 0x12D53 10724 bytes