Malicious PDF — malware analysis report

Static analysis result for SHA-256 d1035cdbd1a13423…

MALICIOUS

PDF

84.7 KB Created: 2021-09-02 23:11:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: a4f93fde3d47aca975eb9e9e235669cb SHA-1: 4b7585f94fc4e8f1ced94773e4e24a359f21e70b SHA-256: d1035cdbd1a134238aff62bac0c826ccc3e4bbc7ce3cecebb678f5790b1ca005
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of external links, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed for malicious redirection. The ML classifier strongly flagged this PDF as malicious. While no scripts were explicitly extracted, the structure and URL patterns suggest it's intended to lure users to malicious sites, likely as part of a phishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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=hoja+control+tension+arterial+pdf PDF link annotation
    • http://www.skk.com.hk/admin/ckfinder/userfiles/files/pukajiwafebu.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078ee9725e71---18639491482.pdfIn PDF document text
    • https://numen-wow.com/userfiles/cloud//files/mebojope.pdfIn PDF document text
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/1247a920f9d11f41b2b8e534f4214389/dusesiwox.pdfIn PDF document text
    • http://artwatch.ru/userfiles/file/tijoxisoti.pdfIn PDF document text
    • https://nocenzura.space/web/img/podborky/files/75375634147.pdfIn PDF document text
    • https://beautydiction.com/ckfinder/userfiles/files/ronumi.pdfIn PDF document text
    • http://chsbicentennialclassof1976.com/clients/c/c2/c283bfa2537a82fb79a670aa087b4bd4/File/66604136944.pdfIn PDF document text
    • http://canadianartistic.com/userfiles/file/kodanirokusekarupusabu.pdfIn PDF document text
    • http://vtvxm.vn/userfiles/file/41884161878.pdfIn PDF document text
    • https://jennysbooks.com/wp-content/plugins/super-forms/uploads/php/files/9d846be953c4b136b9a6986a0821e629/44047408556.pdfIn PDF document text
    • https://earthchartercities.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607882d5d3615---15945058689.pdfIn PDF document text
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/4af9c385a59b4d126e06e753000f9fd0/42033836692.pdfIn PDF document text
    • http://sgpeo.pl/users//file/fafikilelopu.pdfIn PDF document text
    • http://kripasec.com/userfiles/file/nefuxeratogizales.pdfIn PDF document text
    • http://e-hematologica.com/users//file/xowarexavukivu.pdfIn PDF document text
    • https://wendi101.com/userfiles/file/bamofinifakazuxuwuv.pdfIn PDF document text
    • http://sun-green.de/ckfinder/userfiles/files/6927703712.pdfIn PDF document text
    • https://www.accidentinjurylascruces.com/wp-content/plugins/super-forms/uploads/php/files/aqaigked840ve0lckipo5d10o9/26419183312.pdfIn PDF document text
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/160e338bc9d592---kexegebowevub.pdfIn PDF document text
    • https://shotclock.ca/wp-content/plugins/super-forms/uploads/php/files/e1b1e85e1b7a8c269a1664c4bf13e42a/87305542350.pdfIn PDF document text
    • http://stalmost.pl/userfiles/file/kosubalubizoluf.pdfIn PDF document text
    • http://straub-online.ch/userfiles/files/vakitapobow.pdfIn PDF document text
    • http://assushop.com/userfiles/assushop.com/file/jemevenejuxofituja.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_off0000e014.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE014 20512 bytes
SHA-256: 0ffd5df8e6d79ae50ca508840c57c35d33788a55f56625e286c97ac1bf145992
font_01_sfnt_off0001140f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1140F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012c26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C26 10732 bytes
SHA-256: 4cd5b3b12a666acb860455cf3d28a60a6d3c8b082f2e034b46f4483552cb35a1