Malicious PDF — malware analysis report

Static analysis result for SHA-256 94d93cf1d218e988…

MALICIOUS

PDF

83.2 KB Created: 2021-09-22 18:06:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 5fed1c57708c6e9462b241c7527ac228 SHA-1: c62aae42e892517cc8ec52326187c86f57394f21 SHA-256: 94d93cf1d218e988175677da9efd0017275094ba1c4728c143f831d9a6be4e8d
96 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded URLs, many of which point to compromised WordPress sites or are hosted on disposable domains, indicating a link farm or SEO spamming operation. The ML classifier also flagged this PDF as malicious with high confidence. No scripts were extracted, and the document body was unreadable, limiting the analysis of direct user interaction.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 5

  • 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://advairtech.eu/assets/userfiles/file/mufoserajugo.pdf In PDF document text
    • https://himalmanpower.com/ckfinder/userfiles/files/sebukaveki.pdfIn PDF document text
    • http://diennuocdanang.com/uploads/image/files/nodewewesag.pdfIn PDF document text
    • http://allegroescrow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138efb03c085---76577944471.pdfIn PDF document text
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/16141997714ece---46862523476.pdfIn PDF document text
    • https://rieker-consulting.eu/files/file/54711169090.pdfIn PDF document text
    • http://mertcelikkapi.com/userfiles/file/wuxubimorozuj.pdfIn PDF document text
    • http://mensagemcrista.com.br/ckfinder/userfiles/files/96030783469.pdfIn PDF document text
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/febbf51ac2f8a744175ccafda671f13e/sutagav.pdfIn PDF document text
    • http://gorod-r.com/userfiles/file/xuzebametilufe.pdfIn PDF document text
    • http://hitmet.slektenkaas.com/bilder/file/30925306980.pdfIn PDF document text
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/161421091a5071---kepakamu.pdfIn PDF document text
    • https://a-metal.e-giant.net/archive/file/files/15862986596.pdfIn PDF document text
    • https://bhandarisurgical.com/ckfinder/userfiles/files/62774789330.pdfIn PDF document text
    • http://moscreen.in/cmsfiles/file/sodekunomatuwe.pdfIn PDF document text
    • http://fertilityupdates.com/userfiles/files/30218296978.pdfIn PDF document text
    • http://jiendurancecoaching.com/ckfinder/userfiles/files/23559758182.pdfIn PDF document text
    • http://cabinet-blin.fr/ressource/site-image/files/73652701367.pdfIn PDF document text
    • https://protrialse.eu/files/files/91456682987.pdfIn PDF document text
    • https://supremeroi.com/FCKeditor/file/kupigirunoje.pdfIn PDF document text
    • https://yaofangpeixun.com/upload/files/14125917628.pdfIn PDF document text
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613de17c8b413---xisunobesifojawipok.pdfIn PDF document text
    • http://greenflameenergy.com/userfiles/file/talisifanerekurawuzup.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=sony+xperia+z+ultra+latest+android+versionPDF 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_off0000de8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE8E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f6a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6A0 17912 bytes
SHA-256: 0818ead7e07eabf6ce800266a4a6b60b0f72333a27bd4142560eb2608d31c845
font_02_sfnt_off00012592.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12592 10900 bytes
SHA-256: 06fd144a353c7010658d3adc52cd5998f2a18476bf3660e524735633f3816f1f