Malicious PDF — malware analysis report

Static analysis result for SHA-256 1efa244d0acd585a…

MALICIOUS

PDF

89.2 KB Created: 2021-07-31 20:36:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 3e45a8c6d5e4bd6b2f3f681ac87ce2a6 SHA-1: 1f1a723ed3bdb7daeffd4fb1c5ca69741b81162f SHA-256: 1efa244d0acd585aa55f0a6f3c5e006305fc9e08dc54b431631fa37e050cc0d2
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to compromised WordPress sites, indicating a link farm for SEO poisoning or phishing. Heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' strongly suggest this malicious intent. The ML classifier and ClamAV detection further confirm the malicious nature of the file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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 http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3a2d49b2e0---tetodulavum.pdf In PDF document text
    • http://tingyi-bnb.com/CKEdit/upload/files/94210926452.pdfIn PDF document text
    • https://lymfologi.se/anvandarbilder/221/files/29921137662.pdfIn PDF document text
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160e53cfef26ec---zolugi.pdfIn PDF document text
    • https://tocgia247.com/wp-content/plugins/super-forms/uploads/php/files/qcor8njqplep1qrf2pbjjjs5pj/29445609310.pdfIn PDF document text
    • https://jagamimpi.org/contents//files/nokipebi.pdfIn PDF document text
    • https://www.ptlittleflower.org/wp-content/plugins/super-forms/uploads/php/files/b82m8p8cjk91j3nm5crm0ie0j5/85795830382.pdfIn PDF document text
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/5811a6add11da608fba08effb6f3ef5a/17361914878.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a05b27d867---63679158612.pdfIn PDF document text
    • https://www.hamburgeriaagricola.com/wp-content/plugins/super-forms/uploads/php/files/q9kou72coqq9fdmocohe6galad/19840620088.pdfIn PDF document text
    • http://www.mywil.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160c92a0816f4b---nitadogirinomojijosi.pdfIn PDF document text
    • http://zcapitalcrm.com/app/webroot/uploads/files/18245402192.pdfIn PDF document text
    • https://k-newsletter.com/ckupload/files/66098875084.pdfIn PDF document text
    • https://stewsites.com/wp-content/plugins/super-forms/uploads/php/files/d17fbc7ebe6f68307d3546878417f1e0/55601623065.pdfIn PDF document text
    • http://parkwaywest1974.com/clients/861606/File/rabasazag.pdfIn PDF document text
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/ncbhr15es83vc0jokuejstune5/16966193341.pdfIn PDF document text
    • http://self119.net/upload/userfiles/2021/07/files/210703195533.pdfIn PDF document text
    • https://samiznojmo.cz/wp-content/plugins/super-forms/uploads/php/files/5fdba74ad56e23d264fb966bf786643c/85430045286.pdfIn PDF document text
    • http://nomorecpapmachine.com/userfiles/files/loxizanigifusidunadewobu.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160784a581ed9a---88114322690.pdfIn PDF document text
    • http://www.blackhillsdancecentre.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f3c7381573---popedogovonupepibarexin.pdfIn PDF document text
    • https://stonebuild.bg/f/uploads/files/papuxuwevexibag.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=cremas+hidratantes+para+la+cara+colombiaPDF 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f533.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF533 18356 bytes
SHA-256: d83ce0f61bc8820be41500d0761def704a5ca49a2392a202b0e960550dff6ab5
font_01_sfnt_off000123e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123E4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013bfb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13BFB 10952 bytes
SHA-256: 96fce6092ee566a2ca01ba8a4373a32080551be0aaac0faf4eef55f3dc399fad