Malicious PDF — malware analysis report

Static analysis result for SHA-256 2526c4441aa2ec67…

MALICIOUS

PDF

87.4 KB Created: 2021-07-02 03:54:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: a70eea20b7d24829fc0eab927d63ae4f SHA-1: a4b42480d5d68094c96fdc3b3d58c1537e3c9821 SHA-256: 2526c4441aa2ec673cf5963fe0e2f5fb417d182537b4b18b89ddd82d8815e36f
96 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous compromised WordPress upload directories, a common technique for hosting malicious files or redirecting users. The ML classifier strongly indicated maliciousness, and the structure suggests it's designed to leverage SEO or distribute further payloads. No scripts were extracted, but the heuristic firings clearly indicate a malicious link distribution pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://psfund.org/public/uploads/files/cms_files/suvewatozisawurafadesaro.pdf In PDF document text
    • http://edgewood1962.com/clients/2/2b/2b25cacec04995aba37d275b9c35b4d1/File/tegofe.pdfIn PDF document text
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/d2c339ab0f33c57fa3207368a7a6b5bf/62985976405.pdfIn PDF document text
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9a03665df7---23455032051.pdfIn PDF document text
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/160d9a83cd2832---kesugopinogawolapabora.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/93781066489.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/81ivvcn1afb2qvieffleaf8ev4/sapuxubafadujok.pdfIn PDF document text
    • http://urgentcarepb.net/userfiles/file/68859959361.pdfIn PDF document text
    • https://nscs.org/wp-content/plugins/super-forms/uploads/php/files/8ef04ec36711340026c8b5cff695c1e6/78513885906.pdfIn PDF document text
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/e9b6f41d3268ec518c84bf8be827ae8f/nulaso.pdfIn PDF document text
    • http://handbook.hu/upload/page/file/fenetukejapuzufugexasezez.pdfIn PDF document text
    • http://thebranchoflife.org/clients/3/37/37a84c4c47f147f839b5d5a44bb1b86c/File/sukumozed.pdfIn PDF document text
    • http://fabrykakonwersji.pl/wp-content/plugins/super-forms/uploads/php/files/1042c17c940dcb76daf8e908a56baea4/95897222639.pdfIn PDF document text
    • http://chukysovin.com/img-svc/files/pofojotem.pdfIn PDF document text
    • https://vizzzio.ru/wp-content/plugins/super-forms/uploads/php/files/74fcf4c8099517cf3f44a9fff72a1aab/53507418827.pdfIn PDF document text
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082d9acbd760---92003924915.pdfIn PDF document text
    • https://www.mii.net/wp-content/plugins/super-forms/uploads/php/files/f9f4aaa82c537ec91d41ac2609f25c2e/30534439574.pdfIn PDF document text
    • http://sbkf.org/files/files/nuwuvavodatewepexoredaw.pdfIn PDF document text
    • https://www.lightingsolutionsinc.net/wp-content/plugins/super-forms/uploads/php/files/bbf7caeabe2a887200b8c2c17472916b/jejudinawomexaxi.pdfIn PDF document text
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/160b5c4e4b2169---judirisexobofutabo.pdfIn PDF document text
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b03d111d9f---jeniro.pdfIn PDF document text
    • https://www.enterpriselighting.com/wp-content/plugins/super-forms/uploads/php/files/7ef38ed275864f15628b048c5df9e2c1/miteku.pdfIn PDF document text
    • http://www.next-conseil.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16089f649e53df---xetubedemekasi.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b844318c072---xusolumedutumekadadamona.pdfIn PDF document text
    • https://tipresentoio.it/images/file/barinidujisitidibunol.pdfIn PDF document text
    • http://www.nisbd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089d29c8f3a7---gutajisukemow.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=delayed+justice+shirlee+mccoyPDF 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_off0000f14f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF14F 17508 bytes
SHA-256: 418f0fd2d39cda8684f0b169fdd437f17d15d8be5c2e8672e473d8930334b236
font_01_sfnt_off00011ee6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EE6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000136fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x136FD 10876 bytes
SHA-256: 2a7e549716a52ba3c70104c190d3ac5d786777c208dde27490a675c0924c458c