Malicious PDF — malware analysis report

Static analysis result for SHA-256 af72b4b28c4de2ce…

MALICIOUS

PDF

81.2 KB Created: 2021-09-13 05:46:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 6c6fa922fa2e83e7ac9155b9fec86213 SHA-1: 1ab3d697b85e9a269336c83c274f09f96bdd9ec0 SHA-256: af72b4b28c4de2ce3c88a07f81bd1bed62e9b8051843f34ebcf846d6f5be39cc
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS uploads. The document body is unreadable, but the presence of numerous links and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://aitrans.cn/UploadFile/file/F1202109070118519846.pdf In PDF document text
    • http://sm300159.agchost.com/userfiles/files/sewape.pdfIn PDF document text
    • http://zakuskymoser.cz/www/ckfinder/userfiles/files/tusugamobi.pdfIn PDF document text
    • https://swimproject.eu/wp-content/plugins/super-forms/uploads/php/files/67b2359b24d3ba11fef8453fe7f0e1c3/67731368714.pdfIn PDF document text
    • http://africansafaris-spain.com/FCKeditor/editor/filemanager/connectors/php/connector.php?Command=FileUpload&Type=File&CurrentFolder=%2Ffile/58910580824.pdfIn PDF document text
    • https://mytalk7.com/_UploadFile/Images/file/kotisivilirabaw.pdfIn PDF document text
    • http://daegyung.kr/userfiles/file/20210904003053.pdfIn PDF document text
    • http://shannonlakeestates.org/fck_images/file/61140910590.pdfIn PDF document text
    • https://globalathena.com/ckfinder/userfiles/files/94437537660.pdfIn PDF document text
    • http://gezond-trakteren.nl/kasteel-doornenburg-img/bestandenfile/zipulekudo.pdfIn PDF document text
    • https://icbacademy.com/upload/files/rarumuwaf.pdfIn PDF document text
    • http://thegioichuyendong.info/app/webroot/upload/files/44299741550.pdfIn PDF document text
    • https://www.glasswindowequipment.com/wp-content/plugins/super-forms/uploads/php/files/c4ec4b9030b3d92dd91e3682f656f439/woxumakedudejive.pdfIn PDF document text
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/1612f96170ceb7---zorigotiweko.pdfIn PDF document text
    • https://almuhja.ps/ckfinder/userfiles/files/78268583260.pdfIn PDF document text
    • http://logicamail.it/draft/media/pikozan.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613acec02ca29---velasopajebalexiwozukeri.pdfIn PDF document text
    • http://jarosi.hu/files/file/xutenokepupotaxomufuv.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/61668160754.pdfIn PDF document text
    • http://fcgo.tw/uploadpic/files/sadibosatimolusagogori.pdfIn PDF document text
    • http://kftchem.com/upload/files/tumutumupejemosegekamani.pdfIn PDF document text
    • http://euro-ex.com/images/blog/file/19738234395.pdfIn PDF document text
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/161302df3d786d---zaxovatuzojiwos.pdfIn PDF document text
    • http://cleversystems.ru/userfiles/file/38300811376.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=redmi+note+10+ultra+launch+date+in+indiaPDF 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_off0000d731.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD731 10788 bytes
SHA-256: 8749b6afbb864de0a54dfc25588e2c688e12810db9e00bdb7b3b03c2b3e22983
font_01_sfnt_off0000efd6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFD6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000107e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107E8 17900 bytes
SHA-256: e2de661d4abb954a6ad8f6b6704f9bb37acc6a1cea638e41ed850f639913ee88