Malicious PDF — malware analysis report

Static analysis result for SHA-256 33669bf91b0f56c6…

MALICIOUS

PDF

78.0 KB Created: 2021-09-20 03:18:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 4c9dc34a92c778803ae526dcf15850a7 SHA-1: 8f7a293291e1b25ef14e6f420cadb9398a79bfd0 SHA-256: 33669bf91b0f56c68d444071a535555f0e27730bbfa8e6dfbde8220ec8fda5aa
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier, indicating malicious intent. It contains numerous embedded URLs, many pointing to compromised CMS upload storage or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The presence of these links and the overall structure strongly indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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://psiakocky-potisk.cz/webpagebuilder/ckfinder/userfiles/files/43311639318.pdf In PDF document text
    • http://yuanhebiotech.com/upload/files/28663366038.pdfIn PDF document text
    • http://agriturismolescuderie.eu/userfiles/files/pepiridetegataragupo.pdfIn PDF document text
    • https://ruxthai-guesthouse-chiangmai.com/ckfinder/userfiles/files/75816572630.pdfIn PDF document text
    • https://farmaciasacoor.com/site/upload/file/dotovobevagupomed.pdfIn PDF document text
    • http://nature-revive.org/files/file/xiwebovobizom.pdfIn PDF document text
    • https://webaprint.be/img/file/46445065559.pdfIn PDF document text
    • http://deaprogettazioni.it/userfiles/files/8746149571.pdfIn PDF document text
    • https://opsclown.it/ckfinder/userfiles/files/86960477660.pdfIn PDF document text
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cab5c3f60c---35100345709.pdfIn PDF document text
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/6f1422fa3e9eeb8a44acf743d29499cd/63641930187.pdfIn PDF document text
    • http://lehnerkom.de/images/uploaded/file/xituke.pdfIn PDF document text
    • http://szyldkj.com/luodan/images/userfiles/file/10701494657.pdfIn PDF document text
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16147a9d367864---24512509800.pdfIn PDF document text
    • https://demo.wsbe17hongkong.hk/_bin/ckfinder/userfiles/files/16383162114.pdfIn PDF document text
    • http://prvugkh.ru/uploads/files/53274381000.pdfIn PDF document text
    • https://songod.vn/uploads/image/files/tekajerunow.pdfIn PDF document text
    • http://zhizhencn.com/filespath/files/20210912210353.pdfIn PDF document text
    • http://jplus-ag.com/upload/files/BodyFile__613E3DBB430B1.pdfIn PDF document text
    • https://rosebankprimary.co.za/inc/ckfinder/userfiles/files/20483740117.pdfIn PDF document text
    • http://dienlanhtruongson.com/upload/files/doxamafirusipanukili.pdfIn PDF document text
    • http://goksirlambinowice.pl/img/upload/files/ferizisoviluwugipotuvenek.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=premier+league+firestickPDF 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_off0000cca6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCCA6 17536 bytes
SHA-256: 955fcae25f2bee039d3b23ff6b417c070dcfd5930a3d30b47a96faa4a44cad89
font_01_sfnt_off0000fa6f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA6F 10648 bytes
SHA-256: 86d24bce80f1de85bc771c00bc40a02d6f23470b431f86dda595008bee8824de
font_02_sfnt_off000112e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112E3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1