Malicious PDF — malware analysis report

Static analysis result for SHA-256 8dbb99c3e865a5ae…

MALICIOUS

PDF

73.6 KB Created: 2021-09-26 05:03:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 884a3cc28081dab618e98cf34424d04a SHA-1: bd057c5be21c65f542f78126ffff090bb3cb8f5e SHA-256: 8dbb99c3e865a5ae11361d15f8bb1cc0bb0f269d86ddf92f8f92e44d5c54221e
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. Several heuristics indicate the PDF is part of a link farm, with some links pointing to compromised WordPress uploads, suggesting an attempt to distribute further malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://cafesca.org/ckfinder/userfiles/files/69882205250.pdf In PDF document text
    • http://worldofpacifiers.com/editor_uploads/system/files/fipigazupiwitowuwefu.pdfIn PDF document text
    • https://www.fibertech1.com/my_content/js/ckfinder/userfiles/files/72798526649.pdfIn PDF document text
    • http://shijijiaming.cn/filespath/files/20210904081822.pdfIn PDF document text
    • http://fuhua.tumujike.com/assets/upload/files/202109182210464877.pdfIn PDF document text
    • https://supermagnum-bg.com/userfiles/file/fumobefetukomore.pdfIn PDF document text
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613962baef0fc---41916992830.pdfIn PDF document text
    • http://xn--80aaffebba2apgigwiiececnggk9e4k.xn--p1ai/pict/file/50764753138.pdfIn PDF document text
    • http://bilmatbasim.com/userfiles/file/rexatekoxumap.pdfIn PDF document text
    • http://www.cafeinca.com/img/public/contenido/file/xetunod.pdfIn PDF document text
    • https://schachverein-marchhoefe.ch/fcsr/news/upload/file/mepofir.pdfIn PDF document text
    • https://tfnd.org/wp-content/plugins/super-forms/uploads/php/files/387fa6ffedb1fc889d868e866cbdadb2/34522160237.pdfIn PDF document text
    • http://donleroy.net/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/zokapijabe.pdfIn PDF document text
    • http://indianamartialartsfitness.com/flash/indianamartialartsfitness.com/file/tadizisirogonifijumajug.pdfIn PDF document text
    • http://cartonwrappingmachine.com/userfiles/file/64392057815.pdfIn PDF document text
    • http://sanmorales.es/userfiles/files/99460239741.pdfIn PDF document text
    • https://kaimano.it/file/63698652077.pdfIn PDF document text
    • http://yogathoitrang.com/quangbasanpham/app/webroot/upload/image/files/genidasavudilulagisowo.pdfIn PDF document text
    • http://consorzio-csa.it/userfiles/files/wobipumuj.pdfIn PDF document text
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16141765ad065b---menowawazazudema.pdfIn PDF document text
    • https://investmentskillsgroup.com/images/userfiles/file/67495707936.pdfIn PDF document text
    • http://pololanna.com/user_img/files/70866194666.pdfIn PDF document text
    • https://rawoctane.com/uploads/file/14130124209.pdfIn PDF document text
    • http://playonathletics.com/userfiles/file/34433114685.pdfIn PDF document text
    • https://creativesilhouettes.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16137dff2958ef---29446872228.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=4x+msaa+opengl+es+2.0PDF 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_off0000b8e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB8E2 10696 bytes
SHA-256: 7ed350a6965dd4e4928bb9c7f8706aeee2c1ca6e1fe86e9a63f7d0625196c8ab
font_01_sfnt_off0000d176.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD176 18220 bytes
SHA-256: 07d0b422cc87e9fb07f320c30df278f7e1de428c556292b48fe7fa55bfd4a234
font_02_sfnt_off0000ff1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF1D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1