Malicious PDF — malware analysis report

Static analysis result for SHA-256 3d8ff875067f36b9…

MALICIOUS

PDF

84.9 KB Created: 2021-08-07 03:37:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c28d24c11f8911522a678a4c57571fbe SHA-1: d03a3137cb048857fe3f5ea0f4df378e957a17f7 SHA-256: 3d8ff875067f36b98351cf6d6cb9d23bdcb206c2ad4c61f598ac7fbe6735bd59
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous links to external websites, many of which are hosted on compromised WordPress sites or disposable domains, 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. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document delivery mechanisms.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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 https://archism.ru/uplcv?utm_term=avakin+life+generator
    • http://seednseed.com/admin/fckfiles/file/37742287095.pdf
    • http://geoplan.su/userfiles/file/pinen.pdf
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8ec4dde8d1---zoberonib.pdf
    • http://se-ty.ru/uploads/userfiles/file/tivadoxisupuvafabizufuv.pdf
    • https://institut-arabe.org/ckfinder/userfiles/files/zozeji.pdf
    • http://scandirent-new.ru/uploads/assets/file/xuzajakube.pdf
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/010db4e32eca730075279da2abee6681/49935382874.pdf
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/16075e1748255a---seruboxifu.pdf
    • http://liyangah.com/Upload/file/24133726459.pdf
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085a53dc349f---12888548410.pdf
    • http://belst.by/upload/file/serikumolokudewevagivop.pdf
    • http://kientrucsangtrong.com/plus/files/wugutiwobemijuroz.pdf
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/8ustmp7k41vsp5ebaj181esrbf/kobanejafunugefofi.pdf
    • https://ip-kamera-rendszer.hu/ckfinder/userfiles/files/43983019951.pdf
    • https://jdlpartnerss.com/userfiles/file/kinamonu.pdf
    • https://arerp.kr/data/file///vulavuver.pdf
    • https://suksesunited.com/contents//files/63334635730.pdf
    • https://www.parkgest.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160a01f2ab53da---rinaperopujakanegaji.pdf
    • https://anthonygillant.com/userfiles/file/87446111605.pdf
    • http://weilandensemble.nl/ckfinder/userfiles/files/64980933817.pdf
    • https://www.sadcmedia.com/wp-content/plugins/super-forms/uploads/php/files/81l0v99eg22tjm0vge8um4e23b/sawomuzusekesasube.pdf
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608bb69a3c0b4---pezesowudu.pdf
    • http://doanekeyes.com/userfiles/docs/42839847633.pdf
    • http://criminisiepartners.it/userfiles/files/jelofudulavazoniweru.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_off0000e75d.bin
cc00440f2ef6c68f606de2e940747b5d7f8c4587ed21971aeee092d5d3494285
pdf-font-stream PDF embedded font (sfnt) at offset 0xE75D 17420 bytes
font_01_sfnt_off00011519.bin
495e94e92ee5022cd406d7c67052f133fbf801261ee6534e902446b9c0195900
pdf-font-stream PDF embedded font (sfnt) at offset 0x11519 10360 bytes
font_02_sfnt_off00012cad.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12CAD 16792 bytes