Malicious PDF — malware analysis report

Static analysis result for SHA-256 9ad9880e4c109c93…

MALICIOUS

PDF

87.1 KB Created: 2021-08-26 07:28:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 3ee7ffdd5197acb7e02f9d0c6ea52843 SHA-1: 286a3f3b40e5dc73f24b1a785fcdc42c8e3c70fd SHA-256: 9ad9880e4c109c933ddc1444ba4bba43f1338d183098b6de273808208e8e2681
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a link farm pointing to numerous URLs, many of which are hosted on compromised WordPress sites. The ML classifier strongly indicated maliciousness, and the heuristic firings confirm the presence of external URIs and a link farm structure. The document body is heavily obfuscated and unreadable, suggesting it's not intended for direct user interaction but rather to host malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://crewmak.ru/uplcv?utm_term=primary+reformer+in+ammonia+plant PDF link annotation
    • https://beachesbrewing.com/wp-content/plugins/super-forms/uploads/php/files/4ec76eeabc733b8a471cee5cca93b322/59513102469.pdfIn PDF document text
    • https://welltowork.org/wp-content/plugins/super-forms/uploads/php/files/f84ac6b6a1b51b22e089e2101e6f6aac/vidabovo.pdfIn PDF document text
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c4c19d424e4---85498720102.pdfIn PDF document text
    • https://vildmarksjagt.dk/userfiles/file/zesewujexazap.pdfIn PDF document text
    • https://cosalesrep.com/wp-content/plugins/super-forms/uploads/php/files/03d8686ba131ff425e95f96e633d1e04/79690739829.pdfIn PDF document text
    • https://slaterlighting.com/wp-content/plugins/super-forms/uploads/php/files/9ffc8e2a6bf5ae5dda470b7bc6774ee9/34735781258.pdfIn PDF document text
    • http://worthingtonpark101.com/userimages/92056358627.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/6f79d1d002d52f82b64c5e846fc9246e/daxisozanulutizadoj.pdfIn PDF document text
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079d0d1e85da---31172806269.pdfIn PDF document text
    • https://bokaichenyu.com/upload/files/74519859964.pdfIn PDF document text
    • http://medicamarsala.it/userfiles/files/fatef.pdfIn PDF document text
    • http://gamboeng.com/assets/ckfinder/userfiles/files/jobidid.pdfIn PDF document text
    • http://expertworker.paraleumarian.ro/app/webroot/files/userfiles/files/figajikebigo.pdfIn PDF document text
    • https://sipsib.ru/wp-content/plugins/super-forms/uploads/php/files/8e9b69e60be73f92a910d8ca4fcf74c6/40353923948.pdfIn PDF document text
    • http://massimobertoarchitetto.com/userfiles/files/21722385933.pdfIn PDF document text
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160ad88d17df90---25026578690.pdfIn PDF document text
    • https://bevelec.com/bevelec/dossierMois/file/58750397756.pdfIn PDF document text
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/5b4558d0084158ccd64603de3431f2e5/velepezeroropijegikokum.pdfIn PDF document text
    • http://www.psyforyou.nl/upload/fckeditor/file/rofinotujoxiwatisupukun.pdfIn PDF document text
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607ab859ec85d---ximonar.pdfIn PDF document text
    • https://beautifullifeuk.com/wp-content/plugins/super-forms/uploads/php/files/9c0fa68ede8ef03d5ec275f6af9bd491/lisuxote.pdfIn PDF document text
    • https://menuiserie-sainte-anne.fr/userfiles/file/posilumokuravivatutili.pdfIn PDF document text
    • https://ascinfratech.com/clientprojects/trading/file/fufizuxobi.pdfIn PDF document text
    • https://bancodevida.com/bancodevida/admin/images/image/file/50261397495.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_off0000ed6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED6C 10464 bytes
SHA-256: 969b5a055d4a5af298aa7460dea42638d423aeecc3db1ffad4314282f5c08ba5
font_01_sfnt_off00010521.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10521 18348 bytes
SHA-256: cf6b6951b4a1457946992ec820fb20efbb8bec09a3dba5dc6b31bd188480ceaa
font_02_sfnt_off00013627.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13627 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1