Malicious PDF — malware analysis report

Static analysis result for SHA-256 c9109a7af0f44738…

MALICIOUS

PDF

78.1 KB Created: 2021-09-05 22:56:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 672148b841e2c80278fb1fb071f9ec9b SHA-1: 17ab5f8b544ef877317da53fca78ac48fe1250c4 SHA-256: c9109a7af0f44738bff26156f43893ed186491c4dd52677c9472ec814ac973e9
156 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded URLs, many of which point to compromised WordPress sites or disposable hosting, 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 presence of multiple links to potentially malicious content is the primary indicator of the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/f1ad3d5afb827f19bd127866bff91b78/1463574522.pdf In PDF document text
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079904275073---25523839155.pdfIn PDF document text
    • https://www.charroninc.com/wp-content/plugins/super-forms/uploads/php/files/e01266c0381f58dd65f5c5a31ec254d0/lixilesox.pdfIn PDF document text
    • https://www.helpforbusymums.com/wp-content/plugins/super-forms/uploads/php/files/a25058acd2feef20628ce1c84eb77c57/pilixadepebebosudari.pdfIn PDF document text
    • http://www.zima.snowcat.pl/admin/ckfinder/userfiles/files/86027610712.pdfIn PDF document text
    • http://bannails.com/fckeditor_userfiles/file/rovovilenedodamotevi.pdfIn PDF document text
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ea01f19ec4---sunewebexelevasafonuvumiv.pdfIn PDF document text
    • http://nail-free.com/ckfinder/userfiles/files/xikef.pdfIn PDF document text
    • http://ibtaker.ps/userfiles/file/50564695865.pdfIn PDF document text
    • https://www.propertyadvisersaustralia.com/wp-content/plugins/super-forms/uploads/php/files/1415082fbbd8813940e916161e52e554/32174097388.pdfIn PDF document text
    • http://campfirewtx.org/userfiles/file/56916118035.pdfIn PDF document text
    • https://culturasiapamplona.com/guiarte_userfiles/files/97637309358.pdfIn PDF document text
    • http://ps-chiptuning.hu/userfiles/files/mizuzedusalafogojojobed.pdfIn PDF document text
    • http://stagelight.pl/userfiles/files/kofifuvize.pdfIn PDF document text
    • https://laihouston.com/wp-content/plugins/super-forms/uploads/php/files/bc1bd4b642abe37e411e88eee64f702e/52847705309.pdfIn PDF document text
    • http://songpinhao.com/userfiles/files/xeropazitadefajinex.pdfIn PDF document text
    • http://avandcie-energy.com/ckfinder/userfiles/files/3118442864.pdfIn PDF document text
    • https://censcakmu.org/board/file/files/mupajowo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=subject+verb+agreement+worksheet+for+grade+5+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_off0000c5a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5A3 11752 bytes
SHA-256: 071028ee834781dd0492e121636dbcf29b163a0fb600c9f3cae9053b6749bce7
font_01_sfnt_off0000e144.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE144 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f956.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF956 18884 bytes
SHA-256: 58a8c004585bf20b1bdf3db672094e039da287ff1f838069f0945ab8290f5e45