Malicious PDF — malware analysis report

Static analysis result for SHA-256 efd3f1245162a414…

MALICIOUS

PDF

92.2 KB Created: 2021-07-05 19:47:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 109076ebbb91f98932ea2079b94d2677 SHA-1: 763be2c7f4823a6320dce5103b8923b07f6ce096 SHA-256: efd3f1245162a414d2f03e65905e37f6311a27e66b407618e09cfd8aa7e0bb34
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high probability of malicious intent. It functions as a link farm, with numerous URLs pointing to compromised WordPress sites and disposable domains, suggesting a phishing or malware distribution campaign. The presence of 'utm_term' parameters in some URLs further supports the idea of tracking user interactions for malicious purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://laborke.ru/uplcv?utm_term=interpersonal+communication+and+human+relationships+pdf
    • https://al-wesam.com/userfiles/files/tolitafokijus.pdf
    • https://www.fifatravels.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb4f64c472---3779164540.pdf
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/160bfba320dd9d---tilomebadaliwilusukifir.pdf
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a9598900d5f---50055468736.pdf
    • http://dangkykinhdoanhkiengiang.com/upload/ck/files/21454239377.pdf
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/f19e27010726efd000fdcb1107f2332f/89592400250.pdf
    • http://www.alwaysflorida.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d7c46467bcf---matapevujegapa.pdf
    • http://ylgems.com/file_media/file_image/file/99845916505.pdf
    • http://businessvaluationapp.com//fck_files/file/ziwubafewinilogofow.pdf
    • http://workprohealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076a1633c020---91243615989.pdf
    • http://sam-global.info/files/file/wunogi.pdf
    • http://argol-editions.fr/userfiles/file/xixaxiwexogugulutuvixo.pdf
    • http://lavera.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c161dbba22e---jewiwufeb.pdf
    • http://go-pxl.com/uploads/files/90325627125.pdf
    • https://www.adelaarenergy.com/wp-content/plugins/super-forms/uploads/php/files/5tluftpumd5fn3htiubf7dan0o/wevafozotobenizizapapize.pdf
    • http://sage-chem.com/image/files/20210618_065152.pdf
    • http://langeline.com/ckeditor/upload/files/viwanerubutu.pdf
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609ce0b9291c2---80925552573.pdf
    • https://jnfarley.com/wp-content/plugins/super-forms/uploads/php/files/u97bvjeukv10q9ivql25ajoc24/jadozagofegot.pdf
    • https://infrastone.com/userfiles/files/7447885120.pdf
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b1d323bc6d---toxukapekuzutexiz.pdf
    • http://simonide.org/userfiles/file/89043050285.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000105b5.bin
8445b086fdf66675032c82bc57607d908e2ace1af9e04d0f359c74403c435ae9
pdf-font-stream PDF embedded font (sfnt) at offset 0x105B5 10936 bytes
font_01_sfnt_off00011ed6.bin
148896ab06d034db35d9424623b54f18200006751665f9000e16ea28bfa45cfb
pdf-font-stream PDF embedded font (sfnt) at offset 0x11ED6 16872 bytes
font_02_sfnt_off00014ae0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14AE0 16792 bytes