Malicious PDF — malware analysis report

Static analysis result for SHA-256 f6814e25a46925f7…

MALICIOUS

PDF

69.7 KB Created: 2021-06-06 17:43:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-24
MD5: 5c2a714de2cce01d3e52075d057d72cc SHA-1: 0ddd5fbfc0446c5bf28837b9fd30e1bb8ad4b9fb SHA-256: f6814e25a46925f79cdcff1710a94ae25af7fa32dd626aa11a8197efdc7f71f3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file is detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. It contains numerous embedded links, many pointing to compromised WordPress installations, suggesting a link farm designed to redirect users to malicious content. The document body, though heavily obfuscated, contains a URL that appears to be a lure for a free PDF, likely a pretext for distributing malware.

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://ketchas.ru/uplcv?utm_term=communicating+in+groups+applications+and+skills+11th+edition+pdf+free PDF link annotation
    • https://ddriu.hu/wp-content/plugins/super-forms/uploads/php/files/379e74b84caea622fd507bcaf9cb97c6/birovisufusofuzipasasuvab.pdfIn PDF document text
    • https://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1609f2a18be99b---14719658200.pdfIn PDF document text
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3903fe5cc4---41059971854.pdfIn PDF document text
    • http://unesco-mediain.cz/fckfiles/file/28204683488.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/jeggqcagemapnvs3ipdvcmshp3/povobofokepip.pdfIn PDF document text
    • http://www.lauricedale.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160999ebaa6a7b---29681568655.pdfIn PDF document text
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073f9b8ab479---welenopokunozirekofax.pdfIn PDF document text
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16086c4e99c3f2---refepaxudiruviweru.pdfIn PDF document text
    • https://traveltokiev.com/wp-content/plugins/super-forms/uploads/php/files/t7c1dtl81g8mre1vihg6j31ad2/firuwot.pdfIn PDF document text
    • https://djennebeads.com/nbloom/fckuploads/file/nunisivese.pdfIn PDF document text
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/1607ff167d38e2---sipiwati.pdfIn PDF document text
    • https://baconbites.com/wp-content/plugins/super-forms/uploads/php/files/h10pa14tfrkhtiu9nfjns5ed57/jisidomovuvobozikutureru.pdfIn PDF document text
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/s05pguuo7tg6vrs39jr1prrq94/12435586554.pdfIn PDF document text
    • http://sergey-yushkov.com/pict/file/46660484968.pdfIn PDF document text
    • http://ajarnveerapong.com/UserFiles/file/30045887714.pdfIn PDF document text
    • https://fjordancv.info/wp-content/plugins/super-forms/uploads/php/files/efbfb8b29b398494017c20d07bc5d52d/46231996284.pdfIn PDF document text
    • http://peaceinsrilanka.lk/userfiles/file/76719600349.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_off0000d4cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4CB 5592 bytes
SHA-256: 413efff473fcd256480b693c487e6d2d1849d2901da0ad0c63d07039c2abc9c4
font_01_sfnt_off0000e7a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7A5 9932 bytes
SHA-256: cbdd5c76dd0ac2eab4045ddc657a60d91220349b30ac1851d5033ed6ebd13ea5