Malicious PDF — malware analysis report

Static analysis result for SHA-256 66095c54df6d63f3…

MALICIOUS

PDF

69.1 KB Created: 2021-10-02 11:27:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 4b4eec977b65d2a87a33253e78ac2ccb SHA-1: 07f4c434e69f0282bab57e16f96a94e99860c7dd SHA-256: 66095c54df6d63f3886829f8d1c910aa19d48c427ae8950903a10f62f48292a8
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous websites, many of which are hosted on disposable or compromised domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for human readability but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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 https://dcimx.com/files/17492249492.pdf In PDF document text
    • http://mindatpeace.us/uploads/files/51603704685.pdfIn PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/161460e8c9de5c---dapifidilimukujoferu.pdfIn PDF document text
    • https://elsa-daulte.com/ckfinder/userfiles/files/xubikafudirutasixuwig.pdfIn PDF document text
    • https://sdhouse.info/ckfinder/userfiles/files/26276339625.pdfIn PDF document text
    • http://changwontour.kr/FileData/ckfinder/files/20210924_657F19E34E70D552.pdfIn PDF document text
    • https://adsbudget.net/userfiles/file/sosoliparo.pdfIn PDF document text
    • http://namjapizza.com/app/webroot/files/nezenarapelojemaruvopa.pdfIn PDF document text
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/161396490681d5---17880605520.pdfIn PDF document text
    • http://bigdoughpizza.com/uploads/files/xafawunav.pdfIn PDF document text
    • https://ntc-container.com/upload/files/18913670882.pdfIn PDF document text
    • http://capmar.eu/userfiles/file/57451526939.pdfIn PDF document text
    • http://salkim.com/userfiles/file/tepite.pdfIn PDF document text
    • https://7mark3t2-7aya.com/contents/files/96970589441.pdfIn PDF document text
    • https://editora-arara-azul.com.br/site/admin/ckfinder/userfiles/files/bofejiloberavaga.pdfIn PDF document text
    • https://euronuts2009.ge/files/files/54351741099.pdfIn PDF document text
    • https://chambres-lannion.fr/userfiles/file/lugubobuloworisak.pdfIn PDF document text
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/16148f81ccb249---8945191331.pdfIn PDF document text
    • http://rockycheng.com/ckfinder/userfiles/files/70399458153.pdfIn PDF document text
    • http://sk-uralstroy.ru/uploads/files/86196175773.pdfIn PDF document text
    • http://location-appartement-venise.com/italie_documents/files/69856041687.pdfIn PDF document text
    • https://szelvedojavitasmiskolc.hu/files/files/vojataninok.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=enrich+your+knowledgePDF 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_off0000ad73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD73 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c585.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC585 16456 bytes
SHA-256: 96e080bf3ca58241f1263dd30c74bfa552193f80822ef76f6558276880bcea56
font_02_sfnt_off0000ef73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF73 10596 bytes
SHA-256: c5ba6f2cc8f06c30c8a6d87a322a658cf3a426b0d7c67a73c1747f796070110a