Malicious PDF — malware analysis report

Static analysis result for SHA-256 f53fd944318b0d0c…

MALICIOUS

PDF

83.9 KB Created: 2021-09-01 05:04:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: a5485ddc28842d118b481e375529762e SHA-1: 061ac2efeaafb4d8a9fb771594ceb97fc62abc9f SHA-256: f53fd944318b0d0cf42db521ff65ac91bef9420993a35d841b9d377d57d659e7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9925

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://krisoc.ru/uplcv?utm_term=8+letter+words+starting+with+u PDF link annotation
    • http://dermalab.pl/userfiles/file/timipopokozirasalolakag.pdfIn PDF document text
    • https://aucordechasse.fr/vosImages/dufotetofotaletijaxew.pdfIn PDF document text
    • http://gzky.cn/dubeite/ckfinder/userfiles/files/20210610_141755.pdfIn PDF document text
    • http://whkmradio.com/userfiles/file/torudozakapifelireko.pdfIn PDF document text
    • http://arci-mp.fr/admin/File/pefofox.pdfIn PDF document text
    • https://kasihjp.com/contents//files/warup.pdfIn PDF document text
    • http://elvirajogsi.hu/ckfinder/userfiles/files/rinajavidaduzipelabiw.pdfIn PDF document text
    • https://unique.global/wp-content/plugins/super-forms/uploads/php/files/888ab89a514c8466c0d7f08e01e2c0c8/samat.pdfIn PDF document text
    • https://echipamente-scule.ro/userfiles/file/91324492910.pdfIn PDF document text
    • http://www.psychophonie-tarbes.com/ckfinder/userfiles/files/90970812168.pdfIn PDF document text
    • https://rzfmuhasebe.com/userfiles/file/7879824988.pdfIn PDF document text
    • https://www.funes.gob.ar/ckfinder/userfiles/files/61159148271.pdfIn PDF document text
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/f509f03ce57e069e4766ab038ee9fc3c/dumelokunivuvelaxe.pdfIn PDF document text
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/160e942cb503ff---28659056537.pdfIn PDF document text
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/d85141416c0203780adab2e20a8d7ec8/69063244434.pdfIn PDF document text
    • http://asfalon.com/__files/file/xatisimufexinusufexonetuw.pdfIn PDF document text
    • https://ph2020.org/FCKeditor/file/zexakewos.pdfIn PDF document text
    • https://www.sesc.com.ua/wp-content/plugins/super-forms/uploads/php/files/7rgm3lugrh3u6bbqdfd793idq0/79217698733.pdfIn PDF document text
    • https://bluebeakbranding.com/wp-content/plugins/super-forms/uploads/php/files/602f8f7fe6960bd702e096d17a645897/vixafigozavatuf.pdfIn PDF document text
    • http://modero.vn/upload/files/gewatu.pdfIn PDF document text
    • https://admonks.ru/wp-content/plugins/super-forms/uploads/php/files/d2cea715905c7f88f321f0c5f9e68d81/ximeg.pdfIn PDF document text
    • http://mbcasc.net/imgs/file/gesatiwukeriwolizeten.pdfIn PDF document text
    • http://alburigiott.it/userfiles/files/zafidilikirepisewon.pdfIn PDF document text
    • https://certifiedmoversinc.com/wp-content/plugins/super-forms/uploads/php/files/37e6eabb85ce351ca3a1556a43ef3c36/99762172846.pdfIn PDF document text
    • https://refour.eu/wp-content/plugins/super-forms/uploads/php/files/1f78451b3ba89309b84f41f1c3925b35/54710695627.pdfIn PDF document text
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099e674bceb7---defigebofeposadu.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_off0000e276.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE276 10824 bytes
SHA-256: 981b2a6c3ae21c8ad942a96d41b494261ceb4e3806751f8fcb2103dd24edd23b
font_01_sfnt_off0000fb31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB31 17576 bytes
SHA-256: 3a8d3d9d8404c61762859e85cbbabcc6c00966ab7fba43009fff01f6dd70d478
font_02_sfnt_off000128d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128D5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1