Malicious PDF — malware analysis report

Static analysis result for SHA-256 7f81a9f86d8070fd…

MALICIOUS

PDF

70.7 KB Created: 2021-09-27 19:51:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: b1e4969003f5bdbf11314b3aca66f869 SHA-1: 00c554b58b9fd1d13b81b2e0456737f04f364740 SHA-256: 7f81a9f86d8070fd929045ce25dda507b90628957da1b689c244b734529dbca2
96 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 uploads or disposable hosting, indicating a link farm designed to redirect users. The ML classifier strongly flagged this PDF as malicious. While no scripts were explicitly extracted, the structure and URL patterns suggest an attempt to lead users to malicious sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://garglob.ru/uplcv?utm_term=kindle+unlimited+apk PDF link annotation
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16135fcd19b242---zipikikixo.pdfIn PDF document text
    • http://minhtoangalaxyhotel.vn/app/webroot/files/ckfinder/files/kunidepamilid.pdfIn PDF document text
    • http://dxczx.com/ckfinder/userfiles/files/20210909_000728.pdfIn PDF document text
    • http://mmbc.cz/_data/user_files/file/16658359038.pdfIn PDF document text
    • https://thanaclusterwestgate.leaddeehub.com/userfiles/files/37665062821.pdfIn PDF document text
    • https://cheeselicious.net/UserFiles/file/ruzudatol.pdfIn PDF document text
    • http://www.themixchange.com/userfiles/files/mozezuvi.pdfIn PDF document text
    • http://vakantie-noordlimburg.nl/ckfinder/userfiles/files/75287608721.pdfIn PDF document text
    • http://contelex.it/userfiles/files/44313965644.pdfIn PDF document text
    • https://newtop-eg.com/userfiles/file/midojelerexivatupo.pdfIn PDF document text
    • http://xn--90aoaidn.xn--p1ai/ckfinder/userfiles/files/newokakapesu.pdfIn PDF document text
    • https://lompatjauh.com/contents/files/49887706584.pdfIn PDF document text
    • https://bikeid.net/ckfinder/userfiles/files/dosovolu.pdfIn PDF document text
    • http://theexplorerthai.com/userfiles/files/fozividowifozipefomorema.pdfIn PDF document text
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/8c1a5859404b2e4fc48c02a538b8a6d2/vubax.pdfIn PDF document text
    • http://edilgroupdigiovanni.it/userfiles/files/dibagazunowufibu.pdfIn PDF document text
    • http://www.ctnphrae.com/ckfinder/userfiles/files/xewemuworopem.pdfIn PDF document text
    • https://pacantioquia.org/aym_image/files/86695622379.pdfIn PDF document text
    • https://everywheregenes.com/uploadfile/qu26_qu106_com/files/totelojovuk.pdfIn PDF document text
    • http://kino-profi.com/wp-content/plugins/super-forms/uploads/php/files/b3875c415c6a07326f029d6f296b56ee/75045394462.pdfIn PDF document text
    • http://leebyunghun.org/new/upload/board/files/62984269397.pdfIn PDF document text
    • http://dongkoo.com/uploads/editor/files/65566774542.pdfIn PDF document text
    • http://physocare.com/Images_upload/files/7347848235.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613c9028364cc---bisazudopumera.pdfIn PDF document text
    • http://salondebellezaanamariaromero.es/ckfinder/userfiles/files/47553939699.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_off0000b2b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2B4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cac6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAC6 16892 bytes
SHA-256: 1f100be4ad54b3a72d30f34c8c7ae52e0523c2e0d2626e97f4cff88586e3d404
font_02_sfnt_off0000f63e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF63E 10348 bytes
SHA-256: 505df65d1c518c132b84d2eba6283fcbfee49694261bbc9afffc8d6d6fe94034