Malicious PDF — malware analysis report

Static analysis result for SHA-256 305d95289f827c54…

MALICIOUS

PDF

84.8 KB Created: 2021-09-08 02:12:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: e72eb49d7bc5a7f18627e258e7bfbebb SHA-1: a86033519594c9f448a736d81c4868593dbd3383 SHA-256: 305d95289f827c54382d2e8ffe05a858ed377ca0d46d43898a11c28b9a1ca1c5
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external resources, many of which are hosted on compromised CMS uploads, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, and the document body was unreadable, but the heuristic firings and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://archcosmeticstudio.com.au/wp-content/plugins/super-forms/uploads/php/files/e9ffb78b7988bbb1b69f525ad5be292c/kebepebakib.pdf In PDF document text
    • https://evermoral.hk/upload/file/1625043934.pdfIn PDF document text
    • https://rosenstein.lu/userfiles/files/befunuviwimajiz.pdfIn PDF document text
    • http://intergeored.com/upload/File/69910418255.pdfIn PDF document text
    • https://unchiulmihai.ro/files/fckeditor/file/25136977053.pdfIn PDF document text
    • http://studioriggio.it/userfiles/files/nuvipumaxaj.pdfIn PDF document text
    • https://floridainvestment.cz/files/file/67043839013.pdfIn PDF document text
    • http://cancercareresearch.com/userfiles/file/17610721569.pdfIn PDF document text
    • http://brainbond.ro/userfiles/file/12082704.pdfIn PDF document text
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d8bb924e0ab---xidulif.pdfIn PDF document text
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160964c63a5e96---35294894506.pdfIn PDF document text
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607debdb0dc6a---jevitimosabiroz.pdfIn PDF document text
    • http://hud101.vn/webroot/img/posts/files/xifololidurera.pdfIn PDF document text
    • https://www.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/8b8ddc72a863cd9d896139259300db34/99750105252.pdfIn PDF document text
    • https://bmw-zona.ru/uploads/file/kipilevakidopekito.pdfIn PDF document text
    • http://sys-svinding.dk/userfiles/file/68199599575.pdfIn PDF document text
    • http://studiomarazzi.eu/userfiles/files/zarunoriluvatat.pdfIn PDF document text
    • http://sk4education.com/ckfinder/userfiles/files/favubaz.pdfIn PDF document text
    • http://khocabien.com/uploads/files/mufezafetepom.pdfIn PDF document text
    • https://studio45.live/wp-content/plugins/super-forms/uploads/php/files/rvokpb2c25ribjtl1imuj4rk86/jekamozusoku.pdfIn PDF document text
    • http://www.azurwelcomeservices.com/userfiles/file/vibuvasavo.pdfIn PDF document text
    • http://volamtuyetthe.com/userfiles/file/2217357239.pdfIn PDF document text
    • http://mognational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609cdd1e7f9e2---kavivufujemilajuvogoxopo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=factoring+a+quadratic+with+leading+coefficient+1+worksheetPDF 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_off0000e2ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2EC 18540 bytes
SHA-256: 109d68ecdef5e7f01afbc140ae17d1442d712b75cfc7b93140cef0e1ec83c722
font_01_sfnt_off000112c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112C6 11208 bytes
SHA-256: f9e0c1cf767cd35cee23d7e1f9231b18e669c7f85f4b1938076bff3b6a7e51e8
font_02_sfnt_off00012c97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C97 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1