Malicious PDF — malware analysis report

Static analysis result for SHA-256 87b1a7f1880464c6…

MALICIOUS

PDF

70.4 KB Created: 2021-06-11 07:44:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-24
MD5: a8d9c395328f7728a7707c171ff4182c SHA-1: 1b2bf33b1d112178fa7b3b2e076888a54011bbae SHA-256: 87b1a7f1880464c6cd8b5b065f9ecced1178c4898c18abf81316042bbd713fed
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many hosted on compromised WordPress installations, suggesting a link farm or phishing lure. The presence of embedded URLs and the overall structure point towards an attempt to redirect users to malicious content or exploit vulnerabilities, likely through embedded JavaScript.

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://oniceh.ru/uplcv?utm_term=pdf+to+pdf+compressor+200kb PDF link annotation
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/ce4f522ea7537866336d3ffd887be6b5/96555120904.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/160948adc1e0ae---wanozadalekosenasipajafa.pdfIn PDF document text
    • https://socialacademy.gr/wp-content/plugins/super-forms/uploads/php/files/7e79b958eafca163bfb98621305826c1/69597575739.pdfIn PDF document text
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/lfbto9lgtc6noi1jo98v8lti86/pivitatipaxebidajejixex.pdfIn PDF document text
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/160883826ecea2---kixukapapegu.pdfIn PDF document text
    • https://baoholaodong24.com/userfiles/file/38937265368.pdfIn PDF document text
    • https://bursakaynak.net/userfiles/file/47622032482.pdfIn PDF document text
    • https://alperbehang.nl/userfiles/file/2721082089.pdfIn PDF document text
    • http://www.expertnutritionadvisor.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c772d51ed8---devebibekolurom.pdfIn PDF document text
    • https://geneolock.com/locktactyuma/userfiles/file/vewilozozinesupokofu.pdfIn PDF document text
    • http://kangs78.com/clients/66216/File/joxozuzezodaviloxabija.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16076b1ddf0862---57076123991.pdfIn PDF document text
    • http://asiadomainstore.com/userfiles/file/pajirudevuxesu.pdfIn PDF document text
    • http://for-rent-antwerp.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089aa56c0bdc---dilumebavukazupoxurazad.pdfIn PDF document text
    • http://cyklo-sport-servis.cz/UserFiles/File/jasasazefexat.pdfIn PDF document text
    • http://lateonsettay-sachs.org/userfiles/file/29545357270.pdfIn PDF document text
    • https://globalazeri.az/wp-content/plugins/super-forms/uploads/php/files/5hi018gdav3pf41647l7dk0jf0/kopelofewuxekepeluzude.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d47a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD47A 5536 bytes
SHA-256: 164e5a382632c49409b7859da91cdf25f214d7072598d7b1feca6afa966088ce
font_01_sfnt_off0000e73e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE73E 10812 bytes
SHA-256: ed0e0484379bfdf2463da0ed111d2efdf2f1d36df42104a990af75da4bd25ddb