Malicious PDF — malware analysis report

Static analysis result for SHA-256 3668b58e88638c34…

MALICIOUS

PDF

71.5 KB Created: 2021-09-01 11:00:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 4b0b70f0f2fca079bda815a1d180fda8 SHA-1: a8d873c70b4e1f297a1c163cd0872cf03fbdea94 SHA-256: 3668b58e88638c34e21c442d4cec5c072ee06ad5a7b6a7fab75b484dd557c274
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ClamAV and an ML classifier, and contains embedded JavaScript. It also features a link farm pointing to compromised WordPress upload storage, suggesting an attempt to redirect users to malicious content. The presence of JavaScript indicates potential for further exploitation or payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

Heuristics 7

  • 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.
  • 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 http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610078ffee01b---tokizur.pdf In PDF document text
    • http://toastwarenhuis.nl/app/webroot/files/userfiles/files/zawurizuxi.pdfIn PDF document text
    • http://carscaso.com/js/upload/files/46484761035.pdfIn PDF document text
    • http://yossy.biz/userfiles/file/59200862284.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/qam9id2gp7blbtdvffl9hhjt1c/sibezugenonejafuli.pdfIn PDF document text
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/1609f3d1378a90---sefani.pdfIn PDF document text
    • http://chanakol.com/ckfinder/userfiles/files/kokamuketapiso.pdfIn PDF document text
    • https://www.opdrrustukalac.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c918f2eddbe---26941167221.pdfIn PDF document text
    • https://weyergans-hcc.lv/userfiles/file/tuzevimajawokevixibadax.pdfIn PDF document text
    • http://thesprotia.gr/uploads/file/siwepibowuvugufarevava.pdfIn PDF document text
    • https://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/dkb4ti13cfqc4rmfdbl4f3gv03/4515344149.pdfIn PDF document text
    • http://napiarsaigh.com/images/rojegonisov.pdfIn PDF document text
    • https://tortugafilms.ca/adminfiles/file/41731110604.pdfIn PDF document text
    • http://masterref.ru/editorfiles/file/55149270135.pdfIn PDF document text
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/79b028d8762dc2530989a72ddc9ff343/15877444464.pdfIn PDF document text
    • http://catherine-massage.com/ckfinder/userfiles/files/zufubuvedutesebami.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=olfactory+bulb+limbic+systemPDF 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_off0000b6eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB6EB 16292 bytes
SHA-256: befa1b5effb7022a7c7f73e88ae40d9d1d7ea14b3fd5f32e2a835b167a21e6b0
font_01_sfnt_off0000e062.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE062 10772 bytes
SHA-256: 517ee1193fe42e2c1a7b77993b6b86c914ab6e985c293061adf2a22b565ef6d7
font_02_sfnt_off0000f94f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF94F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1