Malicious PDF — malware analysis report

Static analysis result for SHA-256 e2255fab6bbaae58…

MALICIOUS

PDF

92.8 KB Created: 2021-06-30 09:19:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: f65ca28ccd817708be540546e043a660 SHA-1: d981a0e88960af2fd687bb6aee42f4d78bd0594e SHA-256: e2255fab6bbaae58a9c7b3821d21ca74ff3f4af2e5949ec336740ad06b780a8d
96 Risk Score

Malware Insights

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

The sample is a PDF file that contains numerous links pointing to compromised WordPress sites, specifically leveraging the 'formcraft' plugin's file upload functionality. The ML classifier strongly indicated maliciousness. The presence of multiple distinct hosts and a link farm pattern suggests an attempt to distribute malicious content or redirect users to phishing or exploit sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://huntic.ru/uplcv?utm_term=inflict+meaning+in+malayalam PDF link annotation
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607ba379ccf96---60683784809.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/rpie7lav1n5e0s4fg1pdk696k7/zanesofezasojokawig.pdfIn PDF document text
    • http://winkeleninzundert.nl/uploadimages/files/regojetun.pdfIn PDF document text
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae98fa9c927---liganuzoxirenesusexataxe.pdfIn PDF document text
    • http://piri-piri.pl/ckfinder/userfiles/files/vuvogovunodulunoxil.pdfIn PDF document text
    • http://charivne.info/images/file/48547358338.pdfIn PDF document text
    • http://zhongguohuachun.com/d/files/94793940450.pdfIn PDF document text
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077c55f8bb1f---2770559601.pdfIn PDF document text
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160d325f14e700---fareridazedile.pdfIn PDF document text
    • http://www.socalgreatwhite.com/wp-content/plugins/formcraft/file-upload/server/content/files/160984d1728a43---takinalakimibigotiran.pdfIn PDF document text
    • http://vincityhomes.vn/wp-content/plugins/super-forms/uploads/php/files/gqqng7tqjncop4bv9n68i7otv6/72404842805.pdfIn PDF document text
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608630ff860dd---19091290094.pdfIn PDF document text
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16089422a35670---fekebanefibu.pdfIn PDF document text
    • https://www.beachesbrewing.com/wp-content/plugins/super-forms/uploads/php/files/09aa66a59cdafe11bdace620ad1ecc54/11666518458.pdfIn PDF document text
    • http://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d40b49d79c---83344147382.pdfIn PDF document text
    • https://ceilford.org/wp-content/plugins/super-forms/uploads/php/files/3c86bc9488254afb5107b6545bd3bb29/29864658057.pdfIn PDF document text
    • http://ndt-tl.ru/upload/file/tenivil.pdfIn PDF document text
    • https://www.grandeprairie.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608d095e01a15---74623332954.pdfIn PDF document text
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/js2rcbufg6jjpfiioj5h445s5a/40871929083.pdfIn PDF document text
    • https://electrabicycles.pl/app/webroot/uploads/file/16214436071803.pdfIn PDF document text
    • https://afriqueitnews.com/wp-content/plugins/super-forms/uploads/php/files/485c8657a0efbb906c58dd1ecbd31afa/93354129304.pdfIn PDF document text
    • http://gphs100.com/clients/e/e3/e3ed30f4e85b1ff1e74f61348c82e8eb/File/1136779045.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_off000106b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106B2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011ec4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EC4 18656 bytes
SHA-256: 6dc8d5f473b065af8ec359056e7b38a04b7c5018f5c571ec3d90a800c60cfa28
font_02_sfnt_off00014eb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14EB6 10356 bytes
SHA-256: 9599aa66e0985572d045961046acabf9ed843ff5d9446890859f2fc809e4533b