Malicious PDF — malware analysis report

Static analysis result for SHA-256 358031e52e3e7016…

MALICIOUS

PDF

77.2 KB Created: 2021-06-06 21:44:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-05
MD5: cbfb5b5dda7008e8ba9418053dc8152f SHA-1: f94d6cee55904f70cce5095e0c53277d9d3f7182 SHA-256: 358031e52e3e7016167becd62135f36b015b23f02e3eab29855c7b84b909dbc0
96 Risk Score

Malware Insights

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

This PDF file contains numerous embedded URLs that point to compromised WordPress sites, indicating it functions as a link farm. The ML classifier strongly flagged this PDF as malicious, and the heuristic rules suggest it's designed to lead users to potentially harmful content. The presence of external URIs and link farms on disposable hosting further supports its malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://philabc.ru/uplcv?utm_term=gizmos+student+exploration+water+cycle+answer+key PDF link annotation
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/16087562042a9d---lovixikezumufexa.pdfIn PDF document text
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608a056ef4082---zexerotijale.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/su4apti49iig7tmn04saq2ft61/69467043570.pdfIn PDF document text
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16078bec3110b9---34920057660.pdfIn PDF document text
    • https://www.helpforbusymums.com/wp-content/plugins/super-forms/uploads/php/files/0b6ec34f2a3634d1885a4416f512252f/vetuf.pdfIn PDF document text
    • https://gastrotest.co/ckfinder/userfiles/files/mofinogadej.pdfIn PDF document text
    • https://suma.ca/upload/editor/file/20099758508.pdfIn PDF document text
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/86552288e23f53126901f24306489834/29193228864.pdfIn PDF document text
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/160939ed09561b---3280319643.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/1609cbd2c43ed9---37759724079.pdfIn PDF document text
    • https://tamtam.com.ua/wp-content/plugins/super-forms/uploads/php/files/b4022bd82ed98a6d09bc29666c8b5ac0/buzimo.pdfIn PDF document text
    • http://www.commandinglife.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac5a739dc4a---12782093987.pdfIn PDF document text
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/ff39742818b72faa1913f2524346adf7/rafenifufutepikubazes.pdfIn PDF document text
    • https://aldurra.ly/images-editeur/img/file/97573907665.pdfIn PDF document text
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/8da83c75987d228c23efcaf7d390d7d2/4452404007.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e1ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1EE 5508 bytes
SHA-256: bf037398ce27172570574d150911818e1d92ee8b324630b4ea6955893b13841a
font_01_sfnt_off0000f4b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4B8 10876 bytes
SHA-256: 485c3e812ba1148db915d230f11a31b115459e9288c86e7fdae10c4c02470938
font_02_sfnt_off00011928.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11928 4324 bytes
SHA-256: 05d2457133b820fa77aa358e30e9acfbad3f04c46ced9a37296d9311117db176