Malicious PDF — malware analysis report

Static analysis result for SHA-256 c21571d056bca7fa…

MALICIOUS

PDF

80.2 KB Created: 2021-09-05 01:38:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 45dccfb7bbd8bec1136c41978b552813 SHA-1: 4733e0d6387b0b797e71b1220e040def7dfc777f SHA-256: c21571d056bca7fab1369ebe79144375a9d4bbd63dce857d5c33028dc651a837
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded URLs, many of which point to compromised WordPress sites hosting other PDF files. This structure is characteristic of a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608822ceb3a4b---zokaxunuju.pdf In PDF document text
    • http://fitviewer.biz/files/file/99582968247.pdfIn PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/1e1b4ebbcf82b77178241d64146c9d02/weruregide.pdfIn PDF document text
    • http://hotelclinton.it/userfiles/files/pigikezujezabizosix.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087f0e17ca5a---zavuretutajogebutera.pdfIn PDF document text
    • http://urjabatteries.in/userfiles/file/nabomezosalafe.pdfIn PDF document text
    • https://www.northwoodmedical.ca/wp-content/plugins/super-forms/uploads/php/files/oj8idpc81m8n8617m3sckidp4o/46122938257.pdfIn PDF document text
    • http://anhuifan.com/upload_fck/file/2021-7-13/20210713214302806274.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/dnri323l57i5ai23l7c64g30r5/46045965619.pdfIn PDF document text
    • http://bjzjygj.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/9014660954.pdfIn PDF document text
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac184045f32---47054801304.pdfIn PDF document text
    • https://luxartparquet.com/wp-content/plugins/super-forms/uploads/php/files/320974a5b2fdf348da0a48bd28843002/21331498368.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d455978b0ea---kezubufodemumu.pdfIn PDF document text
    • http://www.justgiveahand.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a2743ee260c---vemux.pdfIn PDF document text
    • http://www.binghan.my/userfiles/file/553646348.pdfIn PDF document text
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/0pi2uaonoho91or9n9doach0me/51242817727.pdfIn PDF document text
    • https://syntellect.ru/Repository/file/78019427748.pdfIn PDF document text
    • http://wittlich-luexem.de/userfiles/file/52607186052.pdfIn PDF document text
    • https://digicpictures.com/downloads/9795114621.pdfIn PDF document text
    • http://apexhealthnutrition.com/newerac2c/userfiles/file/xaguripejarogulisolam.pdfIn PDF document text
    • http://ideviceplus.nl/app/webroot/files/userfiles/files/xibalekova.pdfIn PDF document text
    • https://dangeloremodeling.com/nbloom/fckuploads/file/87859721568.pdfIn PDF document text
    • http://yaqeen-eg.com/userfiles/file/tijirazidexagejerunire.pdfIn PDF document text
    • http://55pluscommunityspecialist.com/userfiles/files/nogugonojagevevigabuj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=has+got+worksheets+pdfPDF 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_off0000d75f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD75F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ef76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF76 10704 bytes
SHA-256: cc70cc37068b970701ebadbccf451262ca0c77c793dba07ef93b7fd534d1de54
font_02_sfnt_off000107ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107FF 16892 bytes
SHA-256: 7e3b9cd0b566a0b3520ad0de8115ace84f591cfa06cf35283a43fb538871ce7e