Malicious PDF — malware analysis report

Static analysis result for SHA-256 bd8b31791bf7cea9…

MALICIOUS

PDF

80.7 KB Created: 2021-09-16 20:57:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 31704a1b66ffbcaa71d6f2679f12f16f SHA-1: 2bdf9232c2c46c4897a042dadab56b32ac1e9885 SHA-256: bd8b31791bf7cea97ac61320e8657f43ad50fda2b8bfeecc8f766cb18a5a3518
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to PDF files hosted on compromised CMS platforms or disposable domains. The ML classifier strongly indicated maliciousness, and the heuristic firings suggest this PDF acts as a link farm. The presence of a 'godzilla defence force download' URL in a benign feed suggests a potential lure or misdirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 5

  • 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://zlataraburmevuckovic.com/files/kibumazemotejo.pdf In PDF document text
    • http://azco.friend-match.com/upload/files/4506272281.pdfIn PDF document text
    • https://sharpconsulting.us/app/webroot/ckfinder/userfiles/files/vanegodomonorijigimiwod.pdfIn PDF document text
    • https://www.horisunmauritius.com/wp-content/plugins/super-forms/uploads/php/files/5a65273e967c970f29ef62aa213d5772/sozivakeko.pdfIn PDF document text
    • https://atlastoursntravels.com/userfiles/file/wemepu.pdfIn PDF document text
    • https://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/a3fef80c4ad2499b1ba724afd2bd6990/mobadupuzojaxuwu.pdfIn PDF document text
    • http://sumosushingrill.com/uploads/files/tifikajaborelagusar.pdfIn PDF document text
    • https://zlato-eu.cz/upload/files/bekolavolopolini.pdfIn PDF document text
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134c4a563d71---monuxi.pdfIn PDF document text
    • https://zniczekowalczyk.com/user_images/file/66335042562.pdfIn PDF document text
    • http://asupuro.com/upload/save_image/files/46244683635.pdfIn PDF document text
    • https://ausztriasi.spawellness.hu/upload/hirlevel/files/69442830665.pdfIn PDF document text
    • http://finance-bulldog.cz/UserFiles/File/samirufededezidenej.pdfIn PDF document text
    • https://servingltda.com/userfiles/file/33111880597.pdfIn PDF document text
    • https://www.jnvhardoi.org/ckfinder/userfiles/files/nikoxaxupa.pdfIn PDF document text
    • http://fuzoku-kyujin.jp/ckfinder/userfiles/files/98054345633.pdfIn PDF document text
    • https://siriusdynamics.com/assets/uploads/files/rawupigewusijujosasufaf.pdfIn PDF document text
    • https://www.speeddating.lt/speeddating/ckfinder/userfiles/files/51152147851.pdfIn PDF document text
    • http://kozelskadm.ru/files/uploads/files/32895297804.pdfIn PDF document text
    • http://quatanggiabao.com/images/uploads/files/27232967008.pdfIn PDF document text
    • http://sllight.ru/design/img/upload/file/77862561144.pdfIn PDF document text
    • http://www.binghan.my/userfiles/file/61968490406.pdfIn PDF document text
    • http://huichem.com/ckfinder/userfiles/files/soromupizone.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=godzilla+defence+force+downloadPDF 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_off0000d2e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2E0 19200 bytes
SHA-256: 527ac8a3fb314308909d1a79600abf3bc87c263065b5390f2ade7de8dfbfcf25
font_01_sfnt_off00010541.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10541 10388 bytes
SHA-256: 20460556c295fc8d60dd5b2fe063e890cec6f930ec80eed4ac7e3738244f40bc
font_02_sfnt_off00011cf9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CF9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1