Malicious PDF — malware analysis report

Static analysis result for SHA-256 b488d9c53f69b174…

MALICIOUS

PDF

81.5 KB Created: 2021-09-18 11:58:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8754f1bf1c00e0991b62dd677dd0e419 SHA-1: 0d6c32fa0b491b8df6d57822e8b3c6bdd7f6276c SHA-256: b488d9c53f69b174db3a8b6785b4203fac81c4015e0f22fc931e9e35647715f2
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The embedded JavaScript is a common technique for executing malicious code within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://crewmak.ru/uplcv?utm_term=best+chess+game+for+android+2021
    • http://regmac.net/userfiles/files/nolije.pdf
    • https://totalmediasolutions.ae/ckfinder/userfiles/files/nabavizit.pdf
    • https://sdhouse.info/ckfinder/userfiles/files/96821625375.pdf
    • http://kanizsakran.hu/userfiles/file/tatuxuvatat.pdf
    • http://xnucleus.com/members/member_images/files/66775916108.pdf
    • http://raegcafe.com/uploads/files/lejemugot.pdf
    • https://specializedfacilitymgt.com/public_html/userfiles/file/gejubev.pdf
    • https://bienenaktuell.com/sites/bienenaktuell.com/files/file/lokope.pdf
    • https://telewebmarketing.com/FCKeditor/file/37011212234.pdf
    • http://izhar-energy.com/userfiles/file/kazizamesalirudopiraw.pdf
    • https://dpengineers.info/admin/userfiles/file/janofokolinajeluwa.pdf
    • http://namlinhchisapa.com/userfiles/image/file/gofeferutirisojakutute.pdf
    • https://anukulagrotech.com/userfiles/file/27242461659.pdf
    • https://intrastorg.com/userfiles/file/kufupuxolexevojuxakujuj.pdf
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/1614197cf1531a---92995869077.pdf
    • http://pspectr.ru/userfiles/file/monazolumefemepisusi.pdf
    • http://prplus4u.com/ckupload/files/ruwefumujupure.pdf
    • https://boucherienabli.com/uploads/FCK_files/file/bodezaragigovoguxudo.pdf
    • https://www.padanguparduotuve.lt/ckfinder/userfiles/files/31249888617.pdf
    • http://hla.vn/upload/files/74921712094.pdf
    • https://thebottombillion.org/business_school/uploads/file/rinodowaj.pdf
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/1613a8116d9fac---mamenemurofulis.pdf
    • http://stsmcc.org/www/js/ckfinder/userfiles/files/7095731180.pdf
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/0b716588d4e3f9f39ac56bb60a5c2677/40998175050.pdf
    • http://kortennis.co.kr/B/ck/ckfinder/userfiles/files/muretefijupefalunovirav.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_off0000d975.bin
ba82f8e2a246aa72c80e804d5ebbcdc01dee1b370bd3060a866fd4a445619d98
pdf-font-stream PDF embedded font (sfnt) at offset 0xD975 17280 bytes
font_01_sfnt_off000105b9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x105B9 16792 bytes
font_02_sfnt_off00011dd0.bin
13bbf450784067ac78a75f49c10c277e5370e390ba66f6b301eafd878596571a
pdf-font-stream PDF embedded font (sfnt) at offset 0x11DD0 11224 bytes