Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca4db022e3b76aa6…

MALICIOUS

PDF

71.3 KB Created: 2021-09-22 13:35:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: fe8d6f86b182e0bf1349dcbe70627d63 SHA-1: a49904ab22d82c2ad04c1d2e406fd25b011cdffd SHA-256: ca4db022e3b76aa6b3e444e29a05dc9a032bc2b6acdf52d25a3014ad0fe1e665
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised or disposable domains, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery. The presence of external URI heuristics and link farm indicators reinforces this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://sukaunited4d.vip/contents/files/benasarusomovugurusovod.pdf In PDF document text
    • https://systematix.pl/userfiles/file/nozefatutixunuze.pdfIn PDF document text
    • https://biomedchita.ru/imeg_master/file/wusodeluwetofob.pdfIn PDF document text
    • https://vetregistr.com/ckfinder/userfiles/files/35516674638.pdfIn PDF document text
    • https://sarna-zapiekanki.pl/ckfinder/userfiles/files/roxor.pdfIn PDF document text
    • https://www.cylinder96.ru/admin/ckfinder/userfiles/files/jufajipa.pdfIn PDF document text
    • http://motopujcovnateplice.cz/userfiles/file/59727868898.pdfIn PDF document text
    • http://infoegrafica.com/userfiles/files/pazosumutabefuwogiko.pdfIn PDF document text
    • http://www.jucadent.es/ckfinder/userfiles/files/3702747978.pdfIn PDF document text
    • http://sibleyestateplanning.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/zinorito.pdfIn PDF document text
    • http://tajesink.com/Uploadfiles/files/46260995661.pdfIn PDF document text
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613154927258e---43583724444.pdfIn PDF document text
    • http://tinhdauvietnam.vn/upload/files/bazasumel.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614921e4140b4---xugedivigasexokilazasel.pdfIn PDF document text
    • http://klick-tipp.at/ckfinder/userfiles/publics/files/17009858961.pdfIn PDF document text
    • http://lukinserv.hu/file/depasonomomedovozu.pdfIn PDF document text
    • http://zsdbiopharm.com/upload/files/90887066402.pdfIn PDF document text
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/161303ab5a0e42---61022638791.pdfIn PDF document text
    • http://okfilm.kr/userData/board/file/mipime.pdfIn PDF document text
    • http://flomojapan.com/upload/files/97521330323.pdfIn PDF document text
    • http://gaushalango.com/uploaded_files/userfiles/files/zuzubilatigerivo.pdfIn PDF document text
    • http://cheliabinsk.realxenon.ru/uploads/files/80179383146.pdfIn PDF document text
    • http://goldartline.ua/userfiles/file/suporivori.pdfIn PDF document text
    • http://delta-serwis.pl/pliki/jegovaziris.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=super+mario+tennis+gba+romPDF 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_off0000b279.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB279 10864 bytes
SHA-256: 8223ef51aed961bd99c87f3fd8ffaa63bd4d38b9be1f708d0e7ab1c6d77632ea
font_01_sfnt_off0000cb53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB53 16888 bytes
SHA-256: 562fdca7b539cb0e9758a6602a464b971805eca8a875dea61af7fa3ee009ff01
font_02_sfnt_off0000f601.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF601 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1