Malicious PDF — malware analysis report

Static analysis result for SHA-256 0f7ef8583bc539b4…

MALICIOUS

PDF

73.2 KB Created: 2021-06-14 01:56:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 11480cfcdda4bd57c5e6362a189f632b SHA-1: 889964f4448a62bb3a35bcdb5ec98a2f62dcaacd SHA-256: 0f7ef8583bc539b44e70ee6d8c7029a387057bc8bac8f5236ba76093ee9b1835
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV. It contains numerous links pointing to compromised WordPress sites, suggesting it's part of a link farm designed to redirect users to malicious content. The presence of embedded URLs and the nature of the heuristics indicate a phishing or malware distribution attempt, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://synerhu.ru/uplcv?utm_term=short+stories+in+spanish+and+english+pdf PDF link annotation
    • https://photographerin.agency/wp-content/plugins/super-forms/uploads/php/files/vkpbt0n99mhnfneu3um6c2dj74/12072463958.pdfIn PDF document text
    • https://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/op8i11ptl32g2jrk0c99ihhr4b/38747312738.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16087fa743e2eb---49374101865.pdfIn PDF document text
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/16083417651f10---lesazawojujosaliwezu.pdfIn PDF document text
    • https://rimsball.com/ckfinder/userfiles/files/kunusatedunizeboselawe.pdfIn PDF document text
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b83a653b143---xezofisowebarewoku.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/4kpijulcogsubce0brr7s7ptvg/56693534965.pdfIn PDF document text
    • http://payassistinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/160725e5343490---71522644538.pdfIn PDF document text
    • https://pointsourcegroup.com/wp-content/plugins/super-forms/uploads/php/files/20ab295b5fa17479f4259262658ada3f/21663777256.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/47f5571e40a781189730f5a2de6705f2/83925136393.pdfIn PDF document text
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/32cef362147ca956e77c3629c3368182/pobenagabofupuzopogorabe.pdfIn PDF document text
    • http://www.festivalmarrakech.info/wp-content/plugins/formcraft/file-upload/server/content/files/1609e18ec590da---jirejomiv.pdfIn PDF document text
    • http://school19-zav.ru/userfiles/file/jutizukebigurelafedetejeb.pdfIn PDF document text
    • https://laser-arena.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1607919b638856---bijeroworoxulajagexixo.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_off0000e235.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE235 5404 bytes
SHA-256: b848bfc58f559875ed87d521d958cf6d4dd2b7048e6656976f061ac9ae968138
font_01_sfnt_off0000f48e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF48E 10356 bytes
SHA-256: 273726bbd882d85dc61e8834528ad935d4e49dabacd811a2c04c027eb2ee45d9