Malicious PDF — malware analysis report

Static analysis result for SHA-256 d8c1182b9818e962…

MALICIOUS

PDF

88.0 KB Created: 2021-09-12 14:53:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 8277a8585a799bdaf36c4212b6bcb432 SHA-1: fc3b9a96678b247a7b70a350ed8a629d4f3d8b6f SHA-256: d8c1182b9818e962c38d3f7882aa57c9a4f14e3077c1e99bf1e31b6431ab7b73
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or are structured as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery. The presence of external URI heuristics and link farm indicators supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://brukikostka.pl/uploads/page/file/dedavukumopewemigede.pdf In PDF document text
    • http://gutachterbewertung.de/userfiles/file/ponasim.pdfIn PDF document text
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136cf369a6d9---44461549749.pdfIn PDF document text
    • https://jensbrode.de/files/file/rufivemagenov.pdfIn PDF document text
    • http://theexplorerthai.com/userfiles/files/14579325710.pdfIn PDF document text
    • http://ourgans.org/userfiles/files/95406068791.pdfIn PDF document text
    • https://yumasri.com/assets/ckfinder/userfiles/files/57226386022.pdfIn PDF document text
    • http://accapierre.it/userfiles/files/zopomubigokadatosapogun.pdfIn PDF document text
    • https://www.mybizwebsites.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c779a0fecd---33989246891.pdfIn PDF document text
    • https://dichvumayphoto.vn/webroot/img/files/nolup.pdfIn PDF document text
    • http://www.mab-solutions.fr/upload/file/19340158818.pdfIn PDF document text
    • https://morabia.fi/images/file/57662046365.pdfIn PDF document text
    • http://paradisetourkorea.com/FileData/ckfinder/files/20210904_661938B2FA3FC610.pdfIn PDF document text
    • https://wonwon.taipei/photo/file/kuwajofixuguna.pdfIn PDF document text
    • http://telek-trans.hu/editor_up/bemexajerazajemit.pdfIn PDF document text
    • https://anna-bel.com/app/webroot/files/userfiles/files/74843092561.pdfIn PDF document text
    • https://www.lindopoint.it/wp-content/plugins/super-forms/uploads/php/files/b5b85563acbf85fb7a16777f35708e54/18231953898.pdfIn PDF document text
    • http://bindashnews.com/userfiles/file/jawowujagomoru.pdfIn PDF document text
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/e93cd12eadc32bc655432bce988a99ae/38859231104.pdfIn PDF document text
    • https://senesi-sklad.cz/userfiles/file/gepuba.pdfIn PDF document text
    • http://exima.kr/userData/board/file/63153827940.pdfIn PDF document text
    • http://group-anons.ru/userfiles/files/gekudizurusep.pdfIn PDF document text
    • https://noriupapildu.lt/ckfinder/userfiles/files/26441921496.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=happy+wheels+play+onlinePDF 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_off0000f511.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF511 10344 bytes
SHA-256: 0664b097aa0b094a7c7804da01f329c942c36109fa46d432b1801c1d67074f62
font_01_sfnt_off00010c5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C5C 18052 bytes
SHA-256: e98feffb57bbfdf0f3ade4fbedd84758a2fbef5d2ea25423beb1d781b2891e68
font_02_sfnt_off00013ade.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13ADE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1