Malicious PDF — malware analysis report

Static analysis result for SHA-256 86d84cbf9859b577…

MALICIOUS

PDF

88.2 KB Created: 2021-06-30 21:49:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: fc0948546fa4f9eae47c9f5870813a40 SHA-1: 646bd19e5ece1f4c2bce4879e0ef566fdb05eb52 SHA-256: 86d84cbf9859b5776336f6f4844e357272107c4e714e7fef38fe92233927f16f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious File

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery. The presence of multiple compromised links and link farm characteristics points towards an attempt to obscure the final malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://amursvoidom.ru/media/files/milegaleke.pdf In PDF document text
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b80b06ecbfd---50799992016.pdfIn PDF document text
    • https://rlvanstory.com/wp-content/plugins/super-forms/uploads/php/files/4815ce219f66d43f647dc5027fdcedeb/44568760176.pdfIn PDF document text
    • https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/8de2239b8f100aaf483832417c0bf812/jalupepupujoputobo.pdfIn PDF document text
    • https://muratay.nl/userfiles/file/77281351965.pdfIn PDF document text
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/160abdd724f602---sukadutob.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/1609770e696b0d---xenimopojotepabanedu.pdfIn PDF document text
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/16086051934cf0---84824849883.pdfIn PDF document text
    • http://kapsalonvogue.nl/files/file/80879162590.pdfIn PDF document text
    • https://leunamgroup.com/wp-content/plugins/super-forms/uploads/php/files/5200770c0ec401777d1d4f206221f855/xolaxosetidako.pdfIn PDF document text
    • https://spherule.org/wp-content/plugins/super-forms/uploads/php/files/5d99b0d7e009b35f158211272409f4e5/35339976546.pdfIn PDF document text
    • https://adbadog.com/wp-content/plugins/super-forms/uploads/php/files/8850d7086583a8faf325209f488297c4/zuwas.pdfIn PDF document text
    • https://centar-znr-zop.hr/wp-content/plugins/formcraft/file-upload/server/content/files/16078f40383836---vuganavupazegubefesipuje.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/160ba50947205a---tuxerezafazu.pdfIn PDF document text
    • http://kalmi.ru/upfiles/files/35287777691.pdfIn PDF document text
    • http://savvyais.com/userfiles/file/ketusevasixif.pdfIn PDF document text
    • https://urbanplace.me/wp-content/plugins/super-forms/uploads/php/files/575284c60989664d6fba1b3c25ed2c6e/mugekiwuli.pdfIn PDF document text
    • http://hoangnamjsc.com/upload/files/lusurazo.pdfIn PDF document text
    • http://inlikeflintlogistics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160792daf40941---29160324874.pdfIn PDF document text
    • http://witnesstherealist.com/wp-content/plugins/super-forms/uploads/php/files/9026a638cc51995bc4750b1b9b9fe20f/fegulesapupekufarobet.pdfIn PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607b301674c04---peniladuzopiposawimabenen.pdfIn PDF document text
    • https://torrentclub.vip/wp-content/plugins/super-forms/uploads/php/files/5ifip7o8d4r5bnt1b4d7ii4qen/45892879235.pdfIn PDF document text
    • https://earthchartercities.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609ec0e290a64---zoxerufa.pdfIn PDF document text
    • http://placc.info/up_image/posadoguw.pdfIn PDF document text
    • https://medok18.ru/wp-content/plugins/super-forms/uploads/php/files/80ee146ccd33f18211528109b9555cd1/notilapuladi.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/eoeu06npncpifh9toc146f9cnv/2750044059.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=passive+grammar+meaningPDF 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_off0000f660.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF660 10256 bytes
SHA-256: c545f574d6bd6ecd65211e193e6345bcdf38f578492d91f3592bc1ce1ba786a5
font_01_sfnt_off00010d5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D5F 17528 bytes
SHA-256: 910bcfdb5b025df2fe197f1b001eb0c812713dc456daeea8c75923e49e067c76
font_02_sfnt_off00013b73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B73 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1