Malicious PDF — malware analysis report

Static analysis result for SHA-256 e3768bb4229674d0…

MALICIOUS

PDF

88.2 KB Created: 2021-10-11 19:20:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 9e0e2584ec7199b8c493289ede681f8e SHA-1: 12cc539083764c17c221e14c608a75f1463443ad SHA-256: e3768bb4229674d091130f3b9fa9c1ce14038a34e557360410c55f71c9385860
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. The document contains numerous external URIs and link farms pointing to potentially compromised websites, indicating an attempt to redirect users to malicious content. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports the malicious intent of distributing links for phishing or malware. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://krisoc.ru/uplcv?utm_term=answers+to+christmas+picture+puzzle+game PDF link annotation
    • http://yarpb.ru/pic/userfile/67100994121.pdfIn PDF document text
    • https://mma-montessori.com/admin/ckfinder/userfiles/files/bokenovirigebutopewak.pdfIn PDF document text
    • http://aerotherminsulation.com/userfiles/file/wogoga.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16150cc4082b29---vogeriw.pdfIn PDF document text
    • https://juvelyrikoscentras.lt/Files/file/wugefapulujuvubokobu.pdfIn PDF document text
    • https://jatransfer.com/userfiles/file/27840994454.pdfIn PDF document text
    • https://toocapen.com/files/jujaxepaguxemavabiso.pdfIn PDF document text
    • http://liebherr-tr.com/userfiles/file/72833819164.pdfIn PDF document text
    • http://poslovniimenik.net/firme_data/files/54088606670.pdfIn PDF document text
    • http://ajivikafinance.com/userfiles/file/seteposapab.pdfIn PDF document text
    • http://grgct.com/ckfinder/userfiles/files/15210572340.pdfIn PDF document text
    • https://cyklo-wellness-penzion-palice.cz/content/worijiduvekevezowavadu.pdfIn PDF document text
    • http://delfosventures.com/userfiles/files/26123700223.pdfIn PDF document text
    • http://canadianartistic.com/userfiles/file/danurejaserubadiwemeniwek.pdfIn PDF document text
    • http://www.terresdescaraibes.fr/file/4471202472.pdfIn PDF document text
    • https://powermailer.in/userfiles/file/60435619467.pdfIn PDF document text
    • http://www.museopizarra.com/ckfinder/userfiles/files/80748143791.pdfIn PDF document text
    • http://kezheng.net/Upload/file/67951645069.pdfIn PDF document text
    • https://www.bosingels.nl/ckfinder/userfiles/files/risinironivolalomux.pdfIn PDF document text
    • https://rtaadmin.mrv-educationservices.com/content_file/files/rurepotujuzegu.pdfIn PDF document text
    • http://multiseal.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/16144f6b56bf4d---45339637985.pdfIn PDF document text
    • http://rockycheng.com/ckfinder/userfiles/files/34672319245.pdfIn PDF document text
    • http://yigang-lin.com/uploads/files/202109050412077061.pdfIn PDF document text
    • https://pristineleather.com/userfiles/file/77259681614.pdfIn PDF document text
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/83987fd48f72c039837c0097f43981b8/judubomunanajoj.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_off0000ecc6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECC6 20048 bytes
SHA-256: 8234a34c4bd723f7f24464e8a0eaf220c88189a741ef9d318ed2b33eb5e13f92
font_01_sfnt_off00012124.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12124 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001393b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1393B 11048 bytes
SHA-256: 23a4fb3b3e4ec560378adb68c69a5696b72de6080b49ec6a6a73747e80dae412