Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc39899e359b474e…

MALICIOUS

PDF

77.0 KB Created: 2021-09-17 19:20:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 4e17c9b7847d8a77110edf0627564b50 SHA-1: 05bc30b6b0414c8b428c2eea1168ed8207a701e0 SHA-256: dc39899e359b474e720b0c2cb36e107a24c4dcc2966ae0aeb915a5427914174d
116 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to external resources, including a raw IP address and compromised CMS upload storage, indicating a likely attempt to distribute further malicious content or phish users. The ML classifier also strongly flagged this PDF as malicious. No scripts were extracted from this sample, and the document body was unreadable.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

Heuristics 6

  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://steklo-shik.ru/userfiles/file/xazut.pdf In PDF document text
    • http://stadion-zarya.ru/ckfinder/userfiles/files/90898173176.pdfIn PDF document text
    • http://www.ochoadentalcare.com/tacgestorcontenidos_ochoa/documentos/file/In PDF document text
    • https://topinsolventa.ro/userfiles/file/23983633376.pdfIn PDF document text
    • http://mocphatreal.com/assets/images/ckfinder/files/75332206224.pdfIn PDF document text
    • https://adian.eus/files/galeria/files/91649442008.pdfIn PDF document text
    • https://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/81dvkemn3uuto2phkss4v9ce4k/jewaxenoruzenupufanin.pdfIn PDF document text
    • http://tavaszitura.eu/userfiles/files/kodurorekijenonamiva.pdfIn PDF document text
    • http://visusmarble.com/images_upload/files/26084433462.pdfIn PDF document text
    • https://okud-istra.hr/userfiles/file/dabaxigexokisateter.pdfIn PDF document text
    • http://ambvetsanprospero.eu/userfiles/files/76331310804.pdfIn PDF document text
    • http://211.129.1.225/system/ckfinder/userfiles/files/33142171953.pdfPDF link annotation
    • https://terracetemayonetim.com/upload/ckfinder/files/95778354288.pdfIn PDF document text
    • http://restavratorstvo.com/ckfinder/userfiles/files/69549030036.pdfIn PDF document text
    • http://myflora888.com/ck_files/files/16427329570.pdfIn PDF document text
    • http://pp-aqua.com/userfiles/files/24243197067.pdfIn PDF document text
    • http://fireprovietnam.net/luutru/files/24691332686.pdfIn PDF document text
    • https://vibangthuaphatlai.net/uploads/files/80792059405.pdfIn PDF document text
    • http://fanta-life.com/userfiles/file/morarokogozupilida.pdfIn PDF document text
    • https://noukos.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1613219f4e1494---fupuromalarivowebotitaxo.pdfIn PDF document text
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613697f6646f8---zobobigalaxunagifamikeka.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=dilwale+dulhania+le+jayenge+movie+download+mp4+hdPDF 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_off0000c47a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC47A 11048 bytes
SHA-256: df2e59f84e97169ff8d5e427dce7edaee9200e3f66837e5700a06fa499108858
font_01_sfnt_off0000ddbb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDBB 18476 bytes
SHA-256: a4ecf4155301a07806e8daac4f591cfdd63f887a267da121d5cc281c7210e258
font_02_sfnt_off00010e65.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E65 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1