Malicious PDF — malware analysis report

Static analysis result for SHA-256 c51d363606991e87…

MALICIOUS

PDF

74.3 KB Created: 2021-06-19 20:41:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: d2ed74e80f44829ce6bc9aac10b58945 SHA-1: 01e85c112d44f4ecd79c29296e4f2cd668477e65 SHA-256: c51d363606991e8746dd52548ef227d5265a76d52283439e830765eadf8d14d7
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to multiple compromised WordPress sites, likely for SEO spam or to host further malicious content. The presence of numerous links on disposable hosting and the use of 'utm_term' parameters suggest a phishing or scam-related lure.

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://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/mnu0dakedf02rn0cgilhauq8j2/14223449844.pdf In PDF document text
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/ba1527269a12e51c4aab18cdb23c8943/47969324995.pdfIn PDF document text
    • http://pvsystreports.com/wp-content/plugins/super-forms/uploads/php/files/ef5jibskj4kha4rsg59qsik0h0/25506074384.pdfIn PDF document text
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/435d95fab36fddf959cb4904348818c6/felufafulaxupere.pdfIn PDF document text
    • https://cedarcreeksauce.com/wp-content/plugins/super-forms/uploads/php/files/cd213cd9a626a822c78bf42ec388c876/xetirafegejafokidiragi.pdfIn PDF document text
    • https://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/d2de44f235c5ed850f654dc0916e8a75/1582696059.pdfIn PDF document text
    • https://jakspravnenapsa.cz/userfiles/file/36185554109.pdfIn PDF document text
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2976c6babc---nolepipuxeragopalix.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/sebudunowaxefuzu.pdfIn PDF document text
    • http://shiokuda1.com/contents//files/62773367448.pdfIn PDF document text
    • https://electrabicycles.pl/app/webroot/uploads/file/16203704934837.pdfIn PDF document text
    • http://pocatellocampfire.com/wp-content/plugins/super-forms/uploads/php/files/3ha549c8f71s62kbglm42sdp79/jakagug.pdfIn PDF document text
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160c1dca6c903b---jabajafupu.pdfIn PDF document text
    • https://gauravkankariya.com/wp-content/plugins/super-forms/uploads/php/files/5jms0euf79b0m25m25dddjhna5/44526498169.pdfIn PDF document text
    • https://jfefood.com/wp-content/plugins/super-forms/uploads/php/files/aa4e72ea7952cff1cbffa578d32dcdc2/96788106952.pdfIn PDF document text
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b79974633eb---55217805707.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/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=candy+crush+soda+saga+unlimited+movesPDF 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_off0000e4fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4FB 5420 bytes
SHA-256: 0b48b4acd4498db99da9ec81e8fc5c5985719a0ec72c15071b0b0db6797d24df
font_01_sfnt_off0000f74b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF74B 10772 bytes
SHA-256: 8aaf24b3550c297d134d0eba586c25a54b350daf53f5c13dbe581d1ca5541211