Malicious PDF — malware analysis report

Static analysis result for SHA-256 5c4b3b0a7ffb329e…

MALICIOUS

PDF

105.7 KB Created: 2021-07-01 21:11:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0bdcc67b458a56821c511a356a807afa SHA-1: 48e7ad8dcbc9f3ad120f838ad7db717aad8b1236 SHA-256: 5c4b3b0a7ffb329e636cc248c20dc298424066f84ca2663aabd4c659b0d2b56d
196 Risk Score

Malware Insights

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

The PDF document exhibits characteristics of a phishing lure, specifically a remote-support tool pretext, as indicated by the 'SE_REMOTE_SUPPORT_LURE' heuristic. It contains numerous external URLs, many pointing to compromised CMS uploads or disposable hosting, suggesting an attempt to distribute malicious content or redirect users to phishing sites. The ML classifier and ClamAV detection further support its malicious nature, likely involving the exploitation of PDF vulnerabilities to execute further stages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9926

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
  • Remote-support tool lure high SE_REMOTE_SUPPORT_LURE
    Document instructs the user to install, open, or connect with a remote-support tool such as AnyDesk, TeamViewer, Quick Assist, or ScreenConnect — high-risk in an unsolicited document
  • 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://allytemp.ru/uplcv?utm_term=introduction+to+medical+terminology+chapter+1+review+answers
    • http://baigeleather.com/userfiles/file/xiwoxafowadamuxawafad.pdf
    • http://93564497.com/userfiles/1410418580.pdf
    • http://banghaija.com/userfiles/file/mawagijizokosin.pdf
    • http://rusiuojigalvoji.lt/wp-content/plugins/formcraft/file-upload/server/content/files/1609dc5b8f056e---basixudevazefewot.pdf
    • http://kfnmsz.com/upfolder/e/files/20210624152322.pdf
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/160bcaae336c87---gevipolebutokutameroged.pdf
    • https://www.albispanaderia.com/wp-content/plugins/super-forms/uploads/php/files/90de7ab036fef3b9908d709d022942a2/32883766434.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb95ed2d4b1---jevokuxad.pdf
    • http://csc0351.com/userfiles/file/20210613001509_t7sopf.pdf
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/16074444c4cf41---23312172483.pdf
    • http://mrmax.ca/clients/9797/File/98798022457.pdf
    • http://agnieszkapawlik.com/userfiles/file/fipapuzad.pdf
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b875bea2954---ruzenewap.pdf
    • https://fellowpeo.com/wp-content/plugins/super-forms/uploads/php/files/c6d7009474f4ca16aa0c235683b15b15/duvexilumozabojepur.pdf
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/2a1a4efffff0a563e5cd37c43dcb5615/zubowewimi.pdf
    • http://immobilieninvestors.eu/userfiles/file/55944140820.pdf
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/ltn8si3dml0m700tsopsajmlq6/mosipotufibejerugon.pdf
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072edd3560f6---rogupulaz.pdf
    • https://diversifiedhumansolutions.com/wp-content/plugins/super-forms/uploads/php/files/0cb3fec03618bbd17f1da230a7f283a6/15778620696.pdf
    • https://youstore21.com/wp-content/plugins/super-forms/uploads/php/files/e96a6a9fe437ffff6e1b06db81a33a2d/xisejalibuvedapazoxazof.pdf
    • https://www.rogierstoel.nl/wp-content/plugins/super-forms/uploads/php/files/in3al7k4ji9hnl3plj1v12covu/15608305580.pdf
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b1f219027f1---jarirefukode.pdf
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb472b2a52f---99121609471.pdf
    • http://redwoodpwr.com/wp-content/plugins/super-forms/uploads/php/files/cqppnd04v1qa9jjm184sp62sj6/49872750336.pdf
    • 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_off000135d1.bin
d2a9ed87e5f6bfa3c144fbfccb6052fcfdd38011c8f74ef1d4cb2b5c346f74bd
pdf-font-stream PDF embedded font (sfnt) at offset 0x135D1 18540 bytes
font_01_sfnt_off00016665.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x16665 16792 bytes
font_02_sfnt_off00017e7c.bin
e1556d580f8a51c16dfd77805cfa7d1e69f74e3fc0727699253c9feb80520fc4
pdf-font-stream PDF embedded font (sfnt) at offset 0x17E7C 11328 bytes