Malicious PDF — malware analysis report

Static analysis result for SHA-256 6422fbc9627d9e94…

MALICIOUS

PDF

88.3 KB Created: 2021-07-27 22:57:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9be6294dd13f80cfce974e7e82151706 SHA-1: 4b1e96a5d8008e07d9b35bb4645b7961d814eceb SHA-256: 6422fbc9627d9e94a11d794acd04b47584299f0c3dfcbf4f300f9a1866165f3f
156 Risk Score

Malware Insights

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

The PDF file contains a link farm with numerous external URLs, many hosted on compromised CMS platforms or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure and URL patterns are consistent with a malicious PDF designed to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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 https://noihoithanhtuan.com/media/ftp/file/47976893660.pdf
    • https://sip7.pl/autoinstalator/sip7.online/wp-content/plugins/super-forms/uploads/php/files/97f984d9216572a4cadd0d94004b8460/kubojowawopibafubav.pdf
    • https://tsydesign.com/userfiles/jws/files/4182624917.pdf
    • https://xaydungdonggia.com/app/webroot/files/images/pages/files/12559476663.pdf
    • https://catherinehourihan.art/wp-content/plugins/super-forms/uploads/php/files/a6405cf032d74d21edcd6b267abec8d8/famufefajuvivoxilisokat.pdf
    • https://atraba-holding.com/userfiles/file/detiresijefubirutawabavom.pdf
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/4543afef8c9039c0c6adb15af9790ecd/fiwufajesozubapofubo.pdf
    • http://ms-krmelin.cz/app/webroot/files/files/4976529635.pdf
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a9b1c385236---vevazofokamuxilo.pdf
    • http://texmet.pl/userimages/file/83494572847.pdf
    • https://www.uniqueartzz.com/wp-content/plugins/super-forms/uploads/php/files/skcmbo73kku4m1c4lp33o6tt2u/digafajep.pdf
    • https://ajansnigde.com/resimler/files/70808337605.pdf
    • https://alshamiltrading.com/alshamilfiles/file/90099034516.pdf
    • http://airconbank.com/upload/fckeditor/file/5360568760.pdf
    • https://rarahil.org.np/ckfinder/userfiles/files/47821748995.pdf
    • http://enricobarraco.com/files/65790708560.pdf
    • https://hardlineconstruct.ro/app/webroot/files/userfiles/files/bowojikawejejudopaf.pdf
    • http://marathon-gexin.com/Uploadfiles/files/4085040831.pdf
    • http://www.pointcookelectrician.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607887e344337---9616506275.pdf
    • http://wedooverseas.com/userfiles/file/68102205373.pdf
    • http://bkdesign.ee/userfiles/file/wasut.pdf
    • http://ytbozhuo.com/upload/file/250311593198.pdf
    • http://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160746373b1916---49691448459.pdf
    • https://fiambreszav.com/wp-content/plugins/super-forms/uploads/php/files/9fdf6e00248b6e110a21e022207c5324/3600914570.pdf
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16083988bcb33f---81505509392.pdf
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a78d349e952---bimuvipapisevizitir.pdf
    • http://hopkinshigh1988.com/clients/75739/File/fanokeb.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=can+you+increase+your+amh+levels
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f5d6.bin
d109aeea8941a6c8804eeecd1691ca1be7d91112cc73fd5fcf3f489e5d5137e0
pdf-font-stream PDF embedded font (sfnt) at offset 0xF5D6 10708 bytes
font_01_sfnt_off00010e3b.bin
f4d3a5807c4db6f9f7848a6aac4881100ac4d858c62fff123069cb76e95d5065
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E3B 17012 bytes
font_02_sfnt_off00013a80.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13A80 16792 bytes