Malicious PDF — malware analysis report

Static analysis result for SHA-256 cfddb4a1d290f242…

MALICIOUS

PDF

78.8 KB Created: 2021-09-02 15:49:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 6ad53c6875bb77f743ad226a7b1d8d11 SHA-1: f7c647a26d77274c8a621cdf463d0dbb5d27f8be SHA-256: cfddb4a1d290f242deb817d0849e85fb95bbd2ed6dd1c9f664a471408ab84dc6
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised CMS uploads and disposable hosting, a common tactic for distributing phishing content or second-stage malware. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or exploitation. While no scripts were directly extracted, the nature of the links suggests potential for JavaScript execution or exploitation of PDF vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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 http://optimaglobal.net/ckupload/files/55193533543.pdf In PDF document text
    • http://tcsklife.com/filespath/files/20210828040741.pdfIn PDF document text
    • https://kfz-gutachter-oliver-schiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/16106eef729e25---kigokodexafanifupuvov.pdfIn PDF document text
    • https://vayamcs.com/content_files/files/66889241343.pdfIn PDF document text
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f175a50ff2---jitenazapapawiwupila.pdfIn PDF document text
    • https://zahnersatz.pl/userfiles/files/71477247934.pdfIn PDF document text
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/ef1drucaa9s5t0gbeb0tkr32dr/viposefiposurimezemipi.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/f60c4ac3d86cd9e55ccc257dafed0cb8/97399561132.pdfIn PDF document text
    • https://odlingfamily.com/userfiles/file/nuzuwutujijadefigiwemire.pdfIn PDF document text
    • http://lambanghieuquangcaogiare.net/vietkiendo/upload/file/lepenepikijigubinefewidi.pdfIn PDF document text
    • http://kingkady.com/uploadfile/files/6681926449.pdfIn PDF document text
    • https://ourlady-schools2.com/userfiles/files/25900062129.pdfIn PDF document text
    • http://myblindz.com/fck_user_files/file/91728312723.pdfIn PDF document text
    • http://staceyasp.com/UserFiles/file/7670189458.pdfIn PDF document text
    • http://hotelalbicia.com/userfiles/file/serogujawerovojixabiz.pdfIn PDF document text
    • http://shethof.ch/cgi-bin/dynamisch/file/81837245912.pdfIn PDF document text
    • http://ayhancevik.com/images_upload/files/43237096131.pdfIn PDF document text
    • https://afra24.com/basefile/afra24/files/gogurim.pdfIn PDF document text
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f729164563---90533295423.pdfIn PDF document text
    • http://halmar.info/userfiles/file/fewalezuwamekixakimifar.pdfIn PDF document text
    • http://abbuffalowings.com/uploads/files/jejasuk.pdfIn PDF document text
    • https://takeorders.online/wp-content/plugins/super-forms/uploads/php/files/8d02041qif8ueuah8on5dvc0fm/3556072290.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606fce25cd727---fanajanin.pdfIn PDF document text
    • https://manage4.realtourvision.com/rtv/ckfinder/userfiles/images/files/99436175217.pdfIn PDF document text
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/160719137b533e---retexagivatimutonidad.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=iso+8015+tolerance+table+pdfPDF link annotation
    • 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_off0000ceff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEFF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e711.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE711 17192 bytes
SHA-256: f868b493f87df6c332a659346ced68c844c3017541488cf5d2056e32eace9694
font_02_sfnt_off000113db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113DB 11128 bytes
SHA-256: 19b1cd9b9e2ab76cd4275d230429e0624b59367a90de167e66602ebf400d73e9