Malicious PDF — malware analysis report

Static analysis result for SHA-256 da5744731b6951ae…

MALICIOUS

PDF

81.7 KB Created: 2021-09-24 05:20:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: b971442ad0f4175dee037e154381a93d SHA-1: cf4d4fe63f42e15e1027b1ef33b3fb49902d3d16 SHA-256: da5744731b6951aec5da2837b071256f68bf5e44d119967c10f6aee5eb4b0215
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded JavaScript is a common technique for initiating malicious actions within PDF documents.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://laborke.ru/uplcv?utm_term=apk+anger+of+stick+5+zombie PDF link annotation
    • https://sjamsul-hidajat.id/ck_uploads/uploads/files/5715810055.pdfIn PDF document text
    • https://limsurempat.com/contents/files/97009850834.pdfIn PDF document text
    • http://countryclaim.cz/userfiles/file/gesozoxoxulusar.pdfIn PDF document text
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/161421e3f896aa---bamura.pdfIn PDF document text
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613999ac60c2e---40025199030.pdfIn PDF document text
    • http://jedzenie365.pl/ckfinder/userfiles/files/gikevorekaf.pdfIn PDF document text
    • http://karinameal.com/imgdish/files/14043463200.pdfIn PDF document text
    • http://medica-eg.com/userfiles/file/sabuguxewenijemuwobasada.pdfIn PDF document text
    • https://matricula.arendic.cl/files/29284288897.pdfIn PDF document text
    • https://efficientinfocomm.com/ckfinder/userfiles/files/venikuzusawi.pdfIn PDF document text
    • https://fsreloading.com/userfiles/files/mewixufozapuxa.pdfIn PDF document text
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614c26ac20c21---nofomola.pdfIn PDF document text
    • http://francescasciortino.it/userfiles/files/14476054165.pdfIn PDF document text
    • http://handsonmontessoripk.com/userfiles/files/12735410083.pdfIn PDF document text
    • http://pmke.cz/pictures/files/67843981190.pdfIn PDF document text
    • http://1qjd.com/upload/files/2021-09-11-14-45-38-6kKozSIJ.pdfIn PDF document text
    • https://cherrychile.cl/cherry/uploads/contenido/files/zaweruxiduvu.pdfIn PDF document text
    • http://embeddedhr.com/ckfinder/userfiles/files/88500115741.pdfIn PDF document text
    • http://holztreppe.pl/userfiles/file/68098688339.pdfIn PDF document text
    • http://enjoy.sk/editor_uploads/system/files/3854824976.pdfIn PDF document text
    • http://sakesushilakehavasu.com/uploads/files/nirus.pdfIn PDF document text
    • http://discus-rus.ru/upl/file/jatusasurukaximuj.pdfIn PDF document text
    • http://nassagroup.org/app/webroot/js/ckfinder/userfiles/files/37731872207.pdfIn 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://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_off0000d7c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7C1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000efd8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFD8 11184 bytes
SHA-256: 626a3960508400b343454238cc3b26f2cd72e35785bc9b30625f7c733852e523
font_02_sfnt_off000109f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109F5 18336 bytes
SHA-256: f232c1b8ae697561557ef0031332765aff73a5bbce1537b871a3c21bfa6c5dd9