Malicious PDF — malware analysis report

Static analysis result for SHA-256 6e337d26015d4522…

MALICIOUS

PDF

81.5 KB Created: 2021-09-03 13:42:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 41a55e682b64c630186613249ad1d24c SHA-1: 37b239ae372dd66fa1e4bfc640a196c5f964bee6 SHA-256: 6e337d26015d4522b996da1fa52f5a5efdee4a1b5311d137b0166f8fb517ac59
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many pointing to compromised CMS uploads or disposable hosting, suggesting it functions as a link farm. The primary goal appears to be directing users to external malicious sites, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://synerhu.ru/uplcv?utm_term=choose+the+topic+sentence+worksheet PDF link annotation
    • http://laros.cz/UserFiles/file/xigul.pdfIn PDF document text
    • http://clinicacomciencia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a3a2c0ee49e---82767021336.pdfIn PDF document text
    • http://precedent.by/_newsite/images_from_html_editor/file/semijusot.pdfIn PDF document text
    • https://n95america.com/wp-content/plugins/super-forms/uploads/php/files/f44f35b5bc99730a73d0fb5045e7f2fa/bozixited.pdfIn PDF document text
    • https://bhsbeacon.com/FCKeditor/file/66694204021.pdfIn PDF document text
    • http://chi-kara.net/Upload/files/jilupibunobilovizilo.pdfIn PDF document text
    • http://ck-tct.ru/userfiles/file/96494726126.pdfIn PDF document text
    • http://acquadiqualita.it/ckfinder/userfiles/files/22181424095.pdfIn PDF document text
    • http://chongros.com/userData/board/file/4038593608.pdfIn PDF document text
    • https://ballestermultiservicios.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba7d006fdb3---melifamerufipa.pdfIn PDF document text
    • http://bsp-plovdiv.org/ckfinder/userfiles/files/65478137429.pdfIn PDF document text
    • http://secretlove.ch/ckfinder/userfiles/files/43596802536.pdfIn PDF document text
    • http://sushistoryus.com/uploads/files/fopexegopufofifin.pdfIn PDF document text
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c9a9db43cb4---36718950382.pdfIn PDF document text
    • https://nevisnews.com/userfiles/8773868672.pdfIn PDF document text
    • https://sanvexe.vn/webroot/img/files/lofowubafi.pdfIn PDF document text
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/16089685873f98---guxedukine.pdfIn PDF document text
    • http://oaklandscreche.ie/userfiles/files/3182549419.pdfIn PDF document text
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fb7cff4b2e1---revudiwumenadumopat.pdfIn PDF document text
    • http://chekeeh.ir/basefile/chekeehir/files/7211398947.pdfIn PDF document text
    • https://dobre-akce.cz/media/files/file/47205973640.pdfIn PDF document text
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/161007bfc1467a---15333898588.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a93d3f32c0f---1762717142.pdfIn PDF document text
    • https://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/1023167004205e03f4e205487edbe790/wodapevudekebelekene.pdfIn PDF document text
    • http://kingsfinancialconsulting.com/userfiles/file/zedijajip.pdfIn PDF document text
    • http://startmatbaa.com/userfiles/file/92779312089.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_off0000da22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA22 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f234.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF234 17960 bytes
SHA-256: 6f80d332559350291014d55ddb2a882ccb301c14d0c9d3d0ff6218d0914f8f08
font_02_sfnt_off00012015.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12015 10472 bytes
SHA-256: 48108d9a72d242c8e84a01009fa9e5bc243ac7cc5f137ae273d184c019d9249d