Malicious PDF — malware analysis report

Static analysis result for SHA-256 b87f8eaf767e9ec6…

MALICIOUS

PDF

77.8 KB Created: 2021-09-05 03:01:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-02
MD5: dfb87213f9799dce616e7fa8691ee349 SHA-1: 4336b7b788c07a64309962de552be8b69b2e7413 SHA-256: b87f8eaf767e9ec671375d82659029c7582d2a052eee2364d0f7318d75f7f596
164 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://art4you.sk/editor_uploads/system/files/59533179220.pdf In PDF document text
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/16125aea137464---zevugazuvelasasevep.pdfIn PDF document text
    • http://aqbnb.com/uploadfile/file/venejepikuvozepotidomu.pdfIn PDF document text
    • http://lamdecal.com/Images_upload/files/buzesodesovitixidewaje.pdfIn PDF document text
    • http://ufnk.fr/app/webroot/files/file/poxuzifawokowabarudalowu.pdfIn PDF document text
    • https://songhong-thudo.com/img/files/ludid.pdfIn PDF document text
    • http://heydarbaba.org/resimler/files/kuvexolenenusipoveped.pdfIn PDF document text
    • http://18554080.com/userfiles/file/vofidowadimadanogevi.pdfIn PDF document text
    • https://stdtekstil.com/upload/ckfinder/files/bewosabolodevezuvivama.pdfIn PDF document text
    • http://www.examnotice.in/uploads/files/65027746390.pdfIn PDF document text
    • http://structurecreative.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa29ebb677a---vegusasanuwegerota.pdfIn PDF document text
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16095b9962f83f---6041472847.pdfIn PDF document text
    • https://hcs1000.org/wp-content/plugins/super-forms/uploads/php/files/728c688c5c9153aaa0780d7d196a113d/buzosixaxuwovimupoda.pdfIn PDF document text
    • https://lotte-ppta.com/beta/assets/file/6583021020.pdfIn PDF document text
    • http://steelbo.com/uploads/admins/u0/files/20210530054439.pdfIn PDF document text
    • https://sportsslife.net/upload/ckfinder/files/roditosozimoderu.pdfIn PDF document text
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/98c565ea130d5df4b906ea83b777a458/menibujeniwamixoxibeko.pdfIn PDF document text
    • https://mygamedaysports.com/wp-content/plugins/super-forms/uploads/php/files/22d8dcaeffaa3eb8cbd3fdd415a1c27b/89686420346.pdfIn PDF document text
    • https://www.isnb.co.uk/wp-content/plugins/super-forms/uploads/php/files/288d8b5f82f7c63d923e1aaa96fc8f96/xiduragekalagofekerafiw.pdfIn PDF document text
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/a96ba7b8dca15121d8028e13fa959a3a/bokozimomesisovad.pdfIn PDF document text
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16083c570555d1---jojutipizunokanum.pdfIn PDF document text
    • http://staresecurity.com/userfiles/file/89342365252.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=vba+macro+code+to+convert+pdf+to+excelPDF 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_off0000cac3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAC3 10800 bytes
SHA-256: 7d141f0be3e18926105f6be5f6dfba09c2f120946d60071ee8092dbf1304f744
font_01_sfnt_off0000e37b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE37B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fb8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB8D 17964 bytes
SHA-256: b9403b5ee87c63646d06188d6ed0f7406cc813d965a7a805e3d9b997566a63c5