Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3cd79899eff5a7c…

MALICIOUS

PDF

95.4 KB Created: 2021-08-23 11:53:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: e65b5e4ede9a0fd5a361cf49fed26577 SHA-1: 76cfd448a3a350246621d68535e2427d7d75f442 SHA-256: a3cd79899eff5a7cdaac4d01ccba5a746af313c673300b4bcdeb94007e728468
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of links, many pointing to domains associated with compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery through these links. No scripts were extracted, and the document body was unreadable, so the rationale is based on the URL analysis and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • 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.
  • 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://ngor2-3.com/file_media/file_image/file/64814799772.pdf In PDF document text
    • http://tubietelbar.hu/uploadfile/murozove.pdfIn PDF document text
    • https://stijsr.com/userfiles/file/beninipidusugodojepi.pdfIn PDF document text
    • http://subventionsbetrug.de/wp-content/plugins/super-forms/uploads/php/files/vaadmekpj1korqs5k87h7o1268/4054379703.pdfIn PDF document text
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607c880f5eb70---vagenuz.pdfIn PDF document text
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/1610a8c056a4fe---59085424214.pdfIn PDF document text
    • http://www.homefacelifters.com/wp-content/plugins/super-forms/uploads/php/files/5054f38682181c27bf0ac324981c8a16/37242009489.pdfIn PDF document text
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160bf139ef16b8---soledakatenepexixifawor.pdfIn PDF document text
    • https://www.oneirishrover.com/wp-content/plugins/super-forms/uploads/php/files/0aa4ca38e99f5d442f05853380a9dab4/zurexukuduvoje.pdfIn PDF document text
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/e67c5589d0c606159d47fc022f4f0bb1/sojelinemexotoja.pdfIn PDF document text
    • http://birminghamseaholmclass63.com/clients/75362/File/kizemibugodaxulimomu.pdfIn PDF document text
    • https://rm-parketi.si/uploads/dipavola.pdfIn PDF document text
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086be6ee5bc8---45710152809.pdfIn PDF document text
    • http://ranaghatpchsschool.org/userfiles/file/riligupitu.pdfIn PDF document text
    • https://www.arphplumbing.co.uk/wp-content/plugins/super-forms/uploads/php/files/m7q4k2egr2vosm94os8s92cbnm/29732446323.pdfIn PDF document text
    • http://bfr-bialapodlaska.pl/userfiles/file/36803668806.pdfIn PDF document text
    • http://cke.hk/userfiles/zunigitarowavufiwikevak.pdfIn PDF document text
    • http://gilendor.cz/userfiles/file/tevefenapitozetivuwepam.pdfIn PDF document text
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607bbe4870435---70297286742.pdfIn PDF document text
    • https://hutechsolar.com/upload/user_upload/files/34519184230.pdfIn PDF document text
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/tg50docegpllf3mkeoi1mfk04p/25532086800.pdfIn PDF document text
    • http://pvsystreports.com/wp-content/plugins/super-forms/uploads/php/files/fuc9ijmc8srthgek2j6a7eq3c3/45302256167.pdfIn PDF document text
    • http://thomasbelldescendants.com/clients/40432/File/fituder.pdfIn PDF document text
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d200bc1314---52379032832.pdfIn PDF document text
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/g945n73hkaq24qf6kpc81c0434/84879795221.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=areas+by+level+ffxivPDF 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_off000111e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111E6 16768 bytes
SHA-256: db52fa212bf7749b29a6b0c46cd20900b1e88a391bba6cae4fc1d89d5a11038e
font_01_sfnt_off00013dde.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13DDE 10288 bytes
SHA-256: 0d667634995ff0612493b817fcbef3eb866567ee9086f80f4141e236d2bfb591
font_02_sfnt_off00015534.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15534 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1