Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b9e6115f69973f0…

MALICIOUS

PDF

84.0 KB Created: 2021-09-20 07:33:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: fbf682e770cc3e93698fb79723e4ed90 SHA-1: 7fc0a04c8879e7442badc0e7ab703561a19136d4 SHA-256: 5b9e6115f69973f05955cc8b5ebfc4ee13745192855228a3d62eae464916c8a5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious File

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable domains, indicating a link farm designed to distribute malicious content or phish users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://sendedianqi.com/upload_fck/file/2021-9-15/20210915172458209008.pdf In PDF document text
    • http://vps73.juicy-group.com/editor_upload_image/file/pigetozogopovanifogesivud.pdfIn PDF document text
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613302b76e188---gevamuxipopafudeburuzop.pdfIn PDF document text
    • https://alkathirilaw.com/userfiles/files/sowetometotituwujal.pdfIn PDF document text
    • http://redigonda.it/userfiles/files/96030528287.pdfIn PDF document text
    • https://parlagame.net/calisma2/files/uploads/35161426421.pdfIn PDF document text
    • https://careerroots.net/ckfinder/userfiles/files/8328964945.pdfIn PDF document text
    • http://venusland.vn/app/webroot/img/files/vabotuwow.pdfIn PDF document text
    • http://insuralead.com/userfiles/file/kitenavi.pdfIn PDF document text
    • http://starfishdowney.com/uploads/files/82551718896.pdfIn PDF document text
    • http://airfa.it/userfiles/file/10261276015.pdfIn PDF document text
    • http://lso-msm.com/userfiles/file/57796460351.pdfIn PDF document text
    • http://wahluenfty.com/userfiles/juxudaletov.pdfIn PDF document text
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/1088a27e0e1efa35645993a82014f95f/zakimogizowakojiloxosolap.pdfIn PDF document text
    • http://dispensapertutti.com/userfiles/files/ludesonije.pdfIn PDF document text
    • https://proff-doors.ru/wp-content/plugins/super-forms/uploads/php/files/4612d443f30746e529a4798961036b03/56153854422.pdfIn PDF document text
    • https://popa.com.br/wp-content/plugins/super-forms/uploads/php/files/d0521b5974bfcd0e5b8f8c6dc7b1fb69/sikuneredobuk.pdfIn PDF document text
    • https://gornjastubica.hr/files/bidexogabop.pdfIn PDF document text
    • http://tehnicgaz.eu/files/file/40150873713.pdfIn PDF document text
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/16134e9fce10b7---nugolunotavoziz.pdfIn PDF document text
    • http://mtecommerce.it/public/news/file/50180650036.pdfIn PDF document text
    • https://gonguyenkhoi.vn/upload/files/pekojibojorerusabati.pdfIn PDF document text
    • http://sivam.pl/files/file/tobevunuwuvude.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=best+android+app+to+add+text+to+videoPDF 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_off0000e530.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE530 10560 bytes
SHA-256: ca16a44446afd1e27bfab164f6ba33fb83b9586ff002ab924f1a47aca8a9f1b8
font_01_sfnt_off0000fd6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD6E 17308 bytes
SHA-256: f6d9c8d42be72db0c9abebcbca5414ee023ee0d35438d708cba8988e326d0600
font_02_sfnt_off00012a28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A28 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1