Malicious PDF — malware analysis report

Static analysis result for SHA-256 5bea5c772fdc3afa…

MALICIOUS

PDF

76.6 KB Created: 2021-09-18 11:55:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 22ff5a71b10e7c133959db04eae870a4 SHA-1: 1c6baff2f5abf2160b62ef60326f075676d49c04 SHA-256: 5bea5c772fdc3afa0571f6c316cfa722eb680bf7ec21a0ef1d780761f1f6f4b2
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, suggesting a link farm or phishing lure. The presence of these links and the nature of the heuristics indicate an attempt to redirect users to potentially harmful content.

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://clickbox.ro/images/file/86744080114.pdf In PDF document text
    • http://vucert.vn/uploads/files/femipuser.pdfIn PDF document text
    • https://netwindowvn.com/uploads/userfiles/file/62386555223.pdfIn PDF document text
    • https://avis-medical.ma/wp-content/plugins/super-forms/uploads/php/files/de7f6f71304ddb510b50c9b2e50a2516/44110073117.pdfIn PDF document text
    • https://gyvatukai.manovonia.lt/images/files/nuludexanesibox.pdfIn PDF document text
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145970d9a01d---rewinatutanedexuk.pdfIn PDF document text
    • https://ysh.my/userfiles/file/44273125769.pdfIn PDF document text
    • http://www.atsamuihaus.com/image/upload/File/tebulakufoz.pdfIn PDF document text
    • http://cana.vn/uploads/userfiles/file/26087726625.pdfIn PDF document text
    • https://ermolino.mebel18.com/uploads/files/wuzipipugedutulinivesata.pdfIn PDF document text
    • https://ofcourselc.com/admin/uploadsfile/kagomaziza.pdfIn PDF document text
    • http://ccsl.asia/files/feferasar.pdfIn PDF document text
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/1613642f417156---boziwavuxogin.pdfIn PDF document text
    • http://zgkimsteszew.pl/img/upload/files/wakitoviruvanatodiguk.pdfIn PDF document text
    • https://seedomoretravel.com/files/files/15950483766.pdfIn PDF document text
    • http://ncfc.com.tr/ckfinder/userfiles/files/24083939454.pdfIn PDF document text
    • http://thuocnam.xyz/images/files/76088646862.pdfIn PDF document text
    • https://okud-istra.hr/userfiles/file/rumexamelelirenubepona.pdfIn PDF document text
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/16142483c5cefa---75040966783.pdfIn PDF document text
    • http://fornacedelia.it/userfiles/files/damekuwize.pdfIn PDF document text
    • https://www.jnvhardoi.org/ckfinder/userfiles/files/nikoxaxupa.pdfIn PDF document text
    • https://soudurelausiere.ca/upload/editor/file/63393022360.pdfIn PDF document text
    • http://hcstonetw.com/uploads/files/202109152133309850.pdfIn PDF document text
    • http://princeverma.in/uploads/files/93737416597.pdfIn PDF document text
    • http://hnhappiness.com/d/files/jejotidufewij.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=candy+manor+home+design+mod+apkPDF 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_off0000bdaf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBDAF 20184 bytes
SHA-256: b8df66c7cc372c5a47856c08608981a92f1d4c34c6e5e1d5b04885d072f06aed
font_01_sfnt_off0000f348.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF348 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010b5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B5F 10932 bytes
SHA-256: e777d5a7e42ce69e1c28515b1efd30828940c0dd6b97e12fc9864cfd2a0c062d