Malicious PDF — malware analysis report

Static analysis result for SHA-256 9de4811f779d7601…

MALICIOUS

PDF

79.7 KB Created: 2021-09-22 23:44:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: e65e01ec5d404e81297f3d534f46c227 SHA-1: 580a747733ed17b2cd2e3fb2f387169a115499a6 SHA-256: 9de4811f779d760165b41ed084536ae103e8765ecf110a0f9ff30b8e5c4d7e3b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs pointing to compromised WordPress sites and other disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the heuristic firings and URL analysis confirm the malicious nature of the document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://medvor.ru/uplcv?utm_term=what+is+cache+junk+files+in+whatsapp PDF link annotation
    • http://tekizolasyon.com/ckfinder/userfiles/files/97803028676.pdfIn PDF document text
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d57352a425---sefupudufolok.pdfIn PDF document text
    • https://regenerativetherapyforpain.com/wp-content/plugins/super-forms/uploads/php/files/379ef8cfe9baabe0bd99569926dcbcea/62233902280.pdfIn PDF document text
    • http://www.centralperdana.com/file/sofofopixalifekodelatijar.pdfIn PDF document text
    • https://principesgs.com/userfiles/file/53711810218.pdfIn PDF document text
    • https://thefertilizergranulators.com/d/files/zojupanewojujafaz.pdfIn PDF document text
    • http://bjqyms.com/filespath/files/20210918165611.pdfIn PDF document text
    • http://gaongonmaiphuong.vn/webroot/img/files/pagulemajafisiwexajaj.pdfIn PDF document text
    • http://hongdanhaudio.com/luutru/files/80353820057.pdfIn PDF document text
    • http://hotel-gerard-dalsace.com/upload/document/35107786785.pdfIn PDF document text
    • https://mmeasar.com/mmeasarfiles/file/joxugopaxo.pdfIn PDF document text
    • https://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/16148909ded32b---waserob.pdfIn PDF document text
    • http://musthighschool.mn/ckfinder/userfiles/files/sijalegowolalamumi.pdfIn PDF document text
    • https://www.padanguparduotuve.lt/ckfinder/userfiles/files/sajopadexifepadelezu.pdfIn PDF document text
    • https://burstallconrad.com/editor_files/file/tazozu.pdfIn PDF document text
    • http://tidomusica.com/uploads/files/202109120404126680.pdfIn PDF document text
    • http://www.cemeba.com/uploads/ckfinder/files/91374059823.pdfIn PDF document text
    • http://bananamusic.tw/uploads/files/202109082037049299.pdfIn PDF document text
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/161415623c3213---17665125625.pdfIn PDF document text
    • https://viettrungson.com/media/Files/5346026199.pdfIn PDF document text
    • http://pujcovnanaradi-tvarozna.cz/userfiles/files/95393632429.pdfIn PDF document text
    • http://betonkeritesek.eu/Content/files/22586023191.pdfIn PDF document text
    • http://marcth.pl/media/fck/file/51311052611.pdfIn PDF document text
    • 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_off0000d53b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD53B 16880 bytes
SHA-256: 3cfe9b2aa51f21bea6c9f6ff656935e218bfe79543c0c5223f061561c832b173
font_01_sfnt_off0000ffea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFEA 10760 bytes
SHA-256: a29d8a047a62fbe9c8c0fa7cf52dfd99c336cd466a692dc68b65035123981658
font_02_sfnt_off000118a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118A5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1