Malicious PDF — malware analysis report

Static analysis result for SHA-256 24550270c83c1da5…

MALICIOUS

PDF

86.3 KB Created: 2021-07-30 22:52:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2f6a21bed25a0269a0d098ea473947f8 SHA-1: 36144fa435999bb9405b86dfd0a3f846298bc3b8 SHA-256: 24550270c83c1da5e61175e4aea0a0eb4408f358a0bedb35a187760c72e8bce7
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and an ML classifier, with heuristics indicating it's a link farm on compromised CMS uploads. The 'SE_INVOICE_LURE' heuristic suggests a phishing pretext. While no scripts were explicitly extracted, the PDF structure and embedded URLs point towards a malicious document designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • 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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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://for-rent-antwerp.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7c19855020---31759337528.pdf
    • http://hysansam.com/fckeditor/userfiles/image/3539245888.pdf
    • http://stkvn.ru/wp-content/plugins/super-forms/uploads/php/files/c0c5e0bc49f61c03059f9afcb59d184a/rebuwirotuvoxuwapamek.pdf
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/8vand81d0pac85dhk161mjlhhc/lumoza.pdf
    • https://mk-sito.it/uploads/file/93465312242.pdf
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/802a199aa265b02929da0014cad9b250/5808772923.pdf
    • https://www.loscam.com/lib_common/ckeditor/ckfinder/userfiles/files/vedeni.pdf
    • https://misionesmedellin2030.com/wp-content/plugins/super-forms/uploads/php/files/e89l73ed6n7cqtgjctm0nbvma0/85732772496.pdf
    • https://stcatherine.ac.ug/wp-content/plugins/formcraft/file-upload/server/content/files/1609dbe3ddaf6a---pinozopotusowaxafodu.pdf
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aabd028a561---81952458011.pdf
    • http://portalpr-b2b.es/img/user///file/_0498102001624685093.pdf
    • http://tensoinox.com/userfiles/files/buvatazavorosivazerinine.pdf
    • http://montpellier-business-plan.eu/mbp/upload/images/images/upload/ckfinder/89788412589.pdf
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/160acf90677283---19123756175.pdf
    • https://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/aefb847e1412e258b999457b11a249e3/60909231777.pdf
    • https://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/6b7f21d0c3e56d5b5f2d249a0c0a42ae/xijen.pdf
    • http://cn-daomeng.com/upload/userfiles/files/13fceb3cda3525f400ef766cbe44d5de.pdf
    • https://zionapostolicministries.org/uploads/file/72990757246.pdf
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087b2a3506dd---28286491753.pdf
    • https://lynnesnaturaltreats.com.au/wp-content/plugins/super-forms/uploads/php/files/ce079bda9c5dbfb536146a769c37a941/21890098923.pdf
    • https://www.taxiserviceh24.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c56dfa9a63a---70260101726.pdf
    • https://cailux.lu/userfiles/files/74376681259.pdf
    • https://saatyapi.com/upload/ckfinder/files/7390293095.pdf
    • https://purpleleafestatebuyers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160894e4b2a924---68144202637.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=how+do+you+write+a+scope+of+work
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ed44.bin
6bbdc816e5071bc85dc661c093344af37b907cd37b34f2acd005a4f95b12f4a4
pdf-font-stream PDF embedded font (sfnt) at offset 0xED44 17316 bytes
font_01_sfnt_off00011a21.bin
6f30f626894c25ebd247b553e30ca64ddddbc766375cbcd147e9f4282e55fcfa
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A21 10848 bytes
font_02_sfnt_off00013368.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13368 16792 bytes