Malicious PDF — malware analysis report

Static analysis result for SHA-256 e5997a416ec1ebd0…

MALICIOUS

PDF

79.3 KB Created: 2021-09-08 02:16:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 7ed8cd148c389bc75c0f6cbe1c7cf83a SHA-1: 0bc8b53499accb9cae5deeb43216353938495147 SHA-256: e5997a416ec1ebd0faa08210cb7b9b418782b2a100dafbbfc15dc30da09bb5f8
96 Risk Score

Malware Insights

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

The PDF contains numerous external links, many hosted on compromised WordPress sites or disposable domains, suggesting a link farm or redirection scheme. The ML classifier strongly indicates maliciousness, and the presence of multiple PDF link farm heuristics points to an attempt to manipulate search engine results or distribute malicious content. No scripts were extracted, but the overall structure and URL distribution are indicative of a malicious campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://nomylo.ru/uplcv?utm_term=subaru+legacy+outback+2008+owners+manual PDF link annotation
    • https://remont-bez-zabot.ru/files/file/gadepewasa.pdfIn PDF document text
    • https://vakukh.ru/wp-content/plugins/super-forms/uploads/php/files/69a8095e9bb2316089f7b99e17052b95/19654297798.pdfIn PDF document text
    • http://urjabatteries.in/userfiles/file/pedudanetozufinujegezalid.pdfIn PDF document text
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c520c90c3d5---vaxejaguzofarolug.pdfIn PDF document text
    • https://bbpartner.cz/userfiles/file/javebozazipig.pdfIn PDF document text
    • https://www.webhisto.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160d9321dd306a---kezujuti.pdfIn PDF document text
    • http://teamwork-poetschke.com/ckfinder/userfiles/files/tepot.pdfIn PDF document text
    • http://abwplazaview.com/uploads/files/nelijebinaz.pdfIn PDF document text
    • http://educasters.co/ckfinder/userfiles/files/8049902240.pdfIn PDF document text
    • https://arihantgranites.in/wp-content/plugins/super-forms/uploads/php/files/mep77b15odbu8p7pc08bmg2mn4/nijupol.pdfIn PDF document text
    • http://champaigncursillo.com/userfiles/file/92447082862.pdfIn PDF document text
    • http://iltorg.ru/upload/file/299006014.pdfIn PDF document text
    • http://vogiantinhmach.com/media/ftp/file/86243522067.pdfIn PDF document text
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160dfd443624e2---29525469881.pdfIn PDF document text
    • https://rrvchefs.com/wp-content/plugins/super-forms/uploads/php/files/5dc9f28c8ebe73e2decef0f119c453b1/96549552346.pdfIn PDF document text
    • http://worksafeorg.com/wp-content/plugins/super-forms/uploads/php/files/rm12c32pb5hgna4n4gc2phk2g1/6377935609.pdfIn PDF document text
    • https://www.indee-r.fr/wp-content/plugins/super-forms/uploads/php/files/13f8cec080ff754fb19cb3c401c1cec8/xafujejarewixopam.pdfIn PDF document text
    • http://canphantich.net/Images_upload/files/5798774631.pdfIn PDF document text
    • https://paeonia.ch/userfiles/files/34692622499.pdfIn PDF document text
    • https://www.penyembuhanholistikreiki.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf81c7be3f9---11511780503.pdfIn PDF document text
    • http://qkmedica.com/uploads/userfiles/file/naviwaroponugomanaw.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_off0000cde0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDE0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e5f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5F2 17704 bytes
SHA-256: b92283c2ac54f7b7dc1f70c80964aaae6e36a9ec3199972e4c7ca5e373dbeece
font_02_sfnt_off00011436.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11436 11540 bytes
SHA-256: 1309ee126eeddce9b3f871b83931ee6268ea03bd1e89f7676715643d2dfbaf76