Malicious PDF — malware analysis report

Static analysis result for SHA-256 f37123353919b0ac…

MALICIOUS

PDF

71.0 KB Created: 2021-06-20 04:23:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-24
MD5: 3b8bd590a3ce850bcb64776d3d344554 SHA-1: 84d9f8ce75d41214d4d56439576690d32e66cd1e SHA-256: f37123353919b0ac5b1398815b1d75ebd8620b0633833dc1fb8d2aff8adc391d
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress sites, a common tactic for distributing phishing lures or malware. ClamAV detection and ML classification strongly indicate malicious intent. The presence of numerous links on potentially compromised CMS upload storage suggests an attempt to obscure the final malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://ontime-taxi.kg/wp-content/plugins/super-forms/uploads/php/files/18d783263d8e129c2cf15e197f7d34d2/36995790834.pdf In PDF document text
    • http://multiseal.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/160baa9445f5c2---30201905102.pdfIn PDF document text
    • https://lerong.vn/wp-content/plugins/super-forms/uploads/php/files/9e010d62158fab9c5af9c1b8995b06f2/7504506984.pdfIn PDF document text
    • http://aivieksteslaivas.lv/userfiles/file/85833238044.pdfIn PDF document text
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1607e9d9547d05---45739828989.pdfIn PDF document text
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1608e6ebe1a749---6429417564.pdfIn PDF document text
    • https://www.asahinadigital.com/wp-content/plugins/super-forms/uploads/php/files/hlt05f5rbj5vg6ee3a9555dd7h/pizefefubisaxunelusif.pdfIn PDF document text
    • https://www.napariverinn.com/wp-content/plugins/super-forms/uploads/php/files/5d4fad5c02e25fb831957e6d5a423417/fibisepakosuxujovated.pdfIn PDF document text
    • https://www.rowtheerne.com/wp-content/plugins/super-forms/uploads/php/files/795a6f82ab8705b97748d462bbd27c38/83161973331.pdfIn PDF document text
    • http://www.zywawiara.pl/pliki/ponavuzepetudoredezoripib.pdfIn PDF document text
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/4a3d2bead3a9f84e05cb5fda0b2cc013/gozaluguwosusakebokuxuz.pdfIn PDF document text
    • https://blindnow.com/userfiles/file/72264494328.pdfIn PDF document text
    • http://iccj.jp/images/uploads/fckeditor/file/10486665528.pdfIn PDF document text
    • https://nikoljski.com/ckfinder/userfiles/files/vugitil.pdfIn PDF document text
    • http://www.canadavisaservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ff2ee2a447---dozotibimamokozofes.pdfIn PDF document text
    • https://diaochue.vn/userfiles/file/98707479617.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=clear+cache+and+data+androidPDF link annotation
    • 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dacf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDACF 4752 bytes
SHA-256: 4091ac40c35959f8637d01d1b4025cca526d5807c1e1a9dabf87e50aa0ceaf3e
font_01_sfnt_off0000eae5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAE5 10700 bytes
SHA-256: 3e59f7a7b46c41a4d1febd2c835160ffa3ea9d12be39c0f5c08486653933864c