Malicious PDF — malware analysis report

Static analysis result for SHA-256 5125fda9b6b5c787…

MALICIOUS

PDF

79.8 KB Created: 2021-09-08 08:14:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: e645406c432c82cb36c038d1ec1408c0 SHA-1: 73d5b1537acf9705eecdc970c79dae0952cb28b8 SHA-256: 5125fda9b6b5c7878fb7a73ad6531d06b7bd987fb72650b406066bb330b77d76
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the nature of the embedded URLs and the heuristic firings point towards a malicious document, potentially delivered via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://noventa.cz/media/files/file/diran.pdf In PDF document text
    • https://pikewallis.no/wp-content/plugins/formcraft/file-upload/server/content/files/1609b9c7f845f6---pilidijenusufizar.pdfIn PDF document text
    • https://angelsstaff.com/uploads/file/bebosisimazixu.pdfIn PDF document text
    • http://studioboscono.it/userfiles/files/tefozevobojelo.pdfIn PDF document text
    • https://europeancustomtailor.com/wp-content/plugins/super-forms/uploads/php/files/b34a584f31fe423aad14e73f82c18461/29996479376.pdfIn PDF document text
    • https://shriayurvednagpur.org/public/ckfinder/userfiles/files/guralivakikipokufulu.pdfIn PDF document text
    • http://northwestpixie-bobs.com/clients/e/e1/e1941a3904c49320334fd90e0ed9e852/File/nutakezozobonuxugumudud.pdfIn PDF document text
    • http://www.catalogodecineargentino.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bedc29306c3---paxikuwotaratemojiz.pdfIn PDF document text
    • http://wisdomtours.net/upload/file/vexini.pdfIn PDF document text
    • http://salukool.ee/upload/userfiles/file/6030587515.pdfIn PDF document text
    • http://theofficefurniturestore.com/ckfinder/userfiles/files/dudukabodigaf.pdfIn PDF document text
    • http://smartraoptics.com/fck_filemanager_upload/file/70203210960.pdfIn PDF document text
    • http://articolo17.it/siti//usr/foto/files/zidujukevebip.pdfIn PDF document text
    • http://vonschickenfremont.com/uploads/files/36650598225.pdfIn PDF document text
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/160db5ddf9cc9f---68015191432.pdfIn PDF document text
    • http://beetsom.com/PROGRAM_FCKeditor_UserFiles/file/67034584361179c01c0093.pdfIn PDF document text
    • http://xn----dtbsgbucafmmaf.xn--p1ai/servimages/editor/files/79457877995.pdfIn PDF document text
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5a5f7e6cf---wifexik.pdfIn PDF document text
    • http://ecohort.com/userfiles/files/nujatorogudiruvipojifi.pdfIn PDF document text
    • https://www.masismarketing.com/wp-content/plugins/super-forms/uploads/php/files/a3e6e8d11ff79eedad3020f359876c52/nabizubelibuxif.pdfIn PDF document text
    • http://abwva.com/uploads/files/waboz.pdfIn PDF document text
    • http://anhuishangbiao.com/upload_fck/file/2021-8-26/20210826101654897685.pdfIn PDF document text
    • http://dalaichau.com/files/60092257957.pdfIn PDF document text
    • https://g3az.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7b9bc1698---93145650427.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=die+fledermaus+score+pdfPDF 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_off0000d088.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD088 19560 bytes
SHA-256: e9440b193842a38afc7a4a22e32d2bc92cd421fb87500cb2e273cb24526fc152
font_01_sfnt_off0001014f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1014F 10680 bytes
SHA-256: e676446435ed9e87d25d1f7e3a113aedc599ea94bbb75fa5c844ca63d5f05888
font_02_sfnt_off000119c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119C6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1