Malicious PDF — malware analysis report

Static analysis result for SHA-256 88d0e53ca47dc96e…

MALICIOUS

PDF

68.0 KB Created: 2021-06-16 01:13:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 3347ffd14a8965fbcfb652e764e1cd08 SHA-1: f6c06cc7f8a2230c5e3778ba781167ab03c4d2de SHA-256: 88d0e53ca47dc96e67a7532f649c04be6cdcaf879fed432e08dacdf972142ec8
96 Risk Score

Malware Insights

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

The PDF document contains a link farm pointing to multiple compromised WordPress sites, suggesting an attempt to distribute malicious content or manipulate search engine results. The ML classifier strongly indicated maliciousness, and the presence of numerous external URIs supports this assessment. No scripts were extracted, but the document's structure and embedded links are indicative of a phishing or content distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://archism.ru/uplcv?utm_term=php+http+basic+authentication PDF link annotation
    • http://braintradingbcn.com/wp-content/plugins/super-forms/uploads/php/files/23eadfbb7104c1967842895584b51212/kilorupezo.pdfIn PDF document text
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/7lrgc6mab21tgrkci072cutnj3/malexogojazozinatajoras.pdfIn PDF document text
    • http://www.atrium-tuiles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acdc8243ca3---xosikader.pdfIn PDF document text
    • http://digifast.cz/userfiles/gigojajudegigun.pdfIn PDF document text
    • https://tecnibat.net/uploads/archivos/94972147697.pdfIn PDF document text
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a559eedf70e---13308085660.pdfIn PDF document text
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/1609251f86fa38---52284718485.pdfIn PDF document text
    • https://maidintown.co.uk/wp-content/plugins/super-forms/uploads/php/files/da7557215715fd9ffe3ef994a3eae64b/55180827981.pdfIn PDF document text
    • https://www.infrascale.com/wp-content/plugins/super-forms/uploads/php/files/42aec2d0a811171ca026c0fc34452eb8/bamonikoxigudepinivev.pdfIn PDF document text
    • http://robwalker.net/fckupload/file/rosajenuzinebeno.pdfIn PDF document text
    • https://www.d-table.com/wp-content/plugins/super-forms/uploads/php/files/57b214b6ed6413f8730dbda95f928cd2/41885519014.pdfIn PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608635690571b---tosafirubi.pdfIn PDF document text
    • https://finatwork.com/userfiles/file/lagot.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_off0000c04b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC04B 4916 bytes
SHA-256: 0a971ed28c735ba06519eb1085cfc42172105fe9cfd4561b0f8cf84f471fbec1
font_01_sfnt_off0000d0e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0E7 10752 bytes
SHA-256: 4b7c27a6d8e3031628434979460c04374578fed3c829dbb5759ab4ad0beeeee7
font_02_sfnt_off0000f45a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF45A 4324 bytes
SHA-256: cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34