Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1c1805eb50e3cb4…

MALICIOUS

PDF

83.7 KB Created: 2021-09-01 00:56:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 49cd97dd46014873b6fc1df793d9817e SHA-1: e51e3c4eef92f4a165a5d21af47a28992dffb90e SHA-256: a1c1805eb50e3cb49963e577418cfe12c208f41fd4c6d2fd68ac7ed3874ae852
156 Risk Score

Malware Insights

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

The PDF file contains numerous links, many pointing to compromised WordPress upload directories, suggesting a link farm designed to redirect users to potentially malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. No scripts were extracted, and the document body was unreadable, but the URL structure and heuristic firings are sufficient to assess the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc91775cf7b---sonaxediganuzid.pdf In PDF document text
    • http://keystoparadise.com/userfiles/files/sedirep.pdfIn PDF document text
    • https://tirthmobile.com/wp-content/plugins/super-forms/uploads/php/files/ibokpc39v0n1n613ccivl3dhsn/84775429639.pdfIn PDF document text
    • https://vietfun.com.vn/wp-content/plugins/super-forms/uploads/php/files/u3o5n8r822pqfrm7ufrj9jtthm/gavikadazitojitinita.pdfIn PDF document text
    • https://ewdel.cz/ckfinder/userfiles/files/reluvimex.pdfIn PDF document text
    • https://ntct.dz/ckfinder/userfiles/files/turagozuwajavujafajetaro.pdfIn PDF document text
    • http://beiwendq.com/userfiles/file/kotim.pdfIn PDF document text
    • http://moiarchitekci.pl/pliki/file/naferidakotalusafeze.pdfIn PDF document text
    • http://graciaindoutama.com/kingkong/userfiles/files/40234164261.pdfIn PDF document text
    • https://hostessima.pl/userfiles/file/gojirixugo.pdfIn PDF document text
    • http://www.bongbansaigon.com/uploads/files/42145250909.pdfIn PDF document text
    • https://eamenfaraz.com/cache/fck_files/file/91935403883.pdfIn PDF document text
    • https://producedepot.us/userfiles/files/bijapilofamisoxogo.pdfIn PDF document text
    • https://samiznojmo.cz/wp-content/plugins/super-forms/uploads/php/files/93c1ab4bc7904c3eeebd9fcd09b11faa/14513265252.pdfIn PDF document text
    • https://acgroupenterprise.com/userfiles/file/95715451110.pdfIn PDF document text
    • http://cheers-gifts.com/userfiles/penalitop.pdfIn PDF document text
    • https://bataretak.com/img/files/file/bizukiwukofalijebunigat.pdfIn PDF document text
    • http://www.predoisiasociatii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160f775db0ff03---levejozazodubozulaw.pdfIn PDF document text
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/12f64e57b88c672a2812dbceda11d76d/gijolone.pdfIn PDF document text
    • https://langestrand.se/anvandarbilder/204/files/vevirotuxi.pdfIn PDF document text
    • https://msr-hudsonproperties.com/wp-content/plugins/super-forms/uploads/php/files/1586ab667ec6a88aea61a220a8080a0a/48076561156.pdfIn PDF document text
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608f2c03b486e---vetevopina.pdfIn PDF document text
    • https://www.actionconstructionjax.com/wp-content/plugins/super-forms/uploads/php/files/ad788a8946a056cba2303b79b8d27b53/32504171027.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=html5+canvas+to+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_off0000e1ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1EF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fa06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA06 10648 bytes
SHA-256: d022189b5500092899ac7866b518503bae30106310c37d2de87bfcd570318c79
font_02_sfnt_off00011275.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11275 17892 bytes
SHA-256: 7cfbfa7fe91ba26fa5303ebea1f5bbe41b5386e5bc3f8ed5e4f9fc0cc1a642f8