Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4773c6274e4a2fa…

MALICIOUS

PDF

69.5 KB Created: 2021-09-27 11:50:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 0d63a9cf35aa0130f29dc91b9ec23598 SHA-1: 5ab6fcb1be2995e430de669bf46269089c3c4e2c SHA-256: a4773c6274e4a2faffca0f3d0c86f5d2b6e7837f8af5bd45a25e0b6441ebe2c1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which are part of link farms hosted on compromised websites or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing or malware distribution sites. No scripts were extracted, but the PDF structure itself is used to host and distribute malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://coretry.ru/uplcv?utm_term=what+is+tethering+on+a+phone PDF link annotation
    • http://nail-free.com/ckfinder/userfiles/files/58097313819.pdfIn PDF document text
    • http://bagliodeimille.it/userfiles/files/22994419112.pdfIn PDF document text
    • http://kondicionery-shodnya.ru/upload_picture/file/45798451795.pdfIn PDF document text
    • https://cliniquemyo.com/userfiles/file/33583061995.pdfIn PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138799644cf2---30906085375.pdfIn PDF document text
    • http://vinhosnorte.com/images/files/dobefubokovotowokozaletes.pdfIn PDF document text
    • https://danfort.lv/userfiles/file/62425992439.pdfIn PDF document text
    • http://saikunghouse.hk/userfiles/gesakiloj.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/161373bd972553---dulokitogutonamokubojud.pdfIn PDF document text
    • http://rasmesafar.net/basefile/basefiles/40219510640.pdfIn PDF document text
    • http://huefpdf.org/upload/file/vetufolalakadojalerasir.pdfIn PDF document text
    • http://gruaszarate.com/ckfinder/userfiles/files/nuzumixozarabudikowan.pdfIn PDF document text
    • http://www.valathors.com/ckfinder/userfiles/files/16938337511.pdfIn PDF document text
    • http://partnerplus30.ru/images/fornews/files/97956205576.pdfIn PDF document text
    • http://gourmethousemacau.com/UploadFilesfile///xiwabasuw.pdfIn PDF document text
    • http://suliaok.com/v15/Upload/file/2021927141936550.pdfIn PDF document text
    • https://pnp-studio.com/fckeditorfiles/file/bisepiwu.pdfIn PDF document text
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/2ab0f2e8cbded97f2145a866e9e22fe8/tabigiraxifob.pdfIn PDF document text
    • https://kaptenhoki.org/contents/files/96790109735.pdfIn PDF document text
    • http://klhl.com/userfiles/file/fenudujumamonogixeduvorum.pdfIn PDF document text
    • https://el-tall.pl/pics/file/xamepaludekowigogat.pdfIn PDF document text
    • http://onelove.cz/file/lifumogukifi.pdfIn PDF document text
    • https://greenfuturevietnam.com/Upload/files/gazozoxelokufubak.pdfIn PDF document text
    • http://thanhcongtechtra.com/upload/files/vutipu.pdfIn PDF document text
    • http://abwhopewell.com/uploads/files/57282314013.pdfIn PDF document text
    • 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_off0000b2f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2F1 10480 bytes
SHA-256: abf0f78fc03e310e1d357f26d95ac9a512b86514dc1171123c49985040bf1537
font_01_sfnt_off0000cac3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAC3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e2d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2D5 15028 bytes
SHA-256: ad6b01196ca7f86bab36d01f5495fd389ed437c4eac775f6cb660879bc2fb6c0