Malicious PDF — malware analysis report

Static analysis result for SHA-256 4013a0bfe24b4751…

MALICIOUS

PDF

70.1 KB Created: 2021-09-10 02:18:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 262d7864de223242cc8457b4990e7439 SHA-1: 5f4324f6b4858d89f13b2b5f319e07bdc6546326 SHA-256: 4013a0bfe24b47515e1b6f03fab98cebde79224aaffa8a1c1686cbccafbba43b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many pointing to compromised WordPress sites, and one external URI with a UTM parameter suggesting tracking for user engagement. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the document's purpose is to host a collection of links, likely to direct users to malicious sites for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://catamma.ru/uplcv?utm_term=how+to+clean+your+phone+internal+storage PDF link annotation
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/161332d6515abc---xovipo.pdfIn PDF document text
    • https://zweefvlieg.net/userfiles/file/48205548005.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/sunabajibet.pdfIn PDF document text
    • https://protrialse.eu/files/files/pofazolixalomin.pdfIn PDF document text
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613399e4f1143---weriwev.pdfIn PDF document text
    • http://klasykarozrywki.pl/public/images/fck/file/61074361426.pdfIn PDF document text
    • http://oa30us.com/userfiles/file/95629630952.pdfIn PDF document text
    • http://sbriz.ru/userfiles/file/zexevenelagadelupizubume.pdfIn PDF document text
    • http://silverk.ru/img/lib/file/21661525783.pdfIn PDF document text
    • http://koovappadyscb.com/ckfinder/userfiles/files/64319298331.pdfIn PDF document text
    • https://jamisonfurnace.ca/userfiles/files/fupuwes.pdfIn PDF document text
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613256edae977---muboxafarifojisad.pdfIn PDF document text
    • http://sangsangins.com/upload/upload/file/sefonatamatop.pdfIn PDF document text
    • https://samsungvrvklima.com/upload/ckfinder/files/63785113113.pdfIn PDF document text
    • https://spa-salon.ru/ckfinder/userfiles/files/velesupi.pdfIn PDF document text
    • http://dainichiji.com/upload_ckr/files/74978673846.pdfIn PDF document text
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613857b1c8056---6260867233.pdfIn PDF document text
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/b58f767e8be1c9ae041577707d39e1bc/zobezif.pdfIn PDF document text
    • http://parateam.cz/file/vodikiloxija.pdfIn PDF document text
    • https://anzhero-sudzhensk.verlauf-ekb.ru/admin/ckfinder/userfiles/files/jegazumasovilamepowepet.pdfIn PDF document text
    • http://naszymsladem.pl/upload/file/godovotafujo.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_off0000b198.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB198 10944 bytes
SHA-256: d30aaff7b7d63cb86046980a06c8ade7f9982b3c71d0502ffc0e483dcf417bbb
font_01_sfnt_off0000caf3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAF3 15760 bytes
SHA-256: 0abf5922ed05f9ef1a41caa5f59a4d57c8fcd7a99d4663ff79c9516c9c27b337
font_02_sfnt_off0000f306.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF306 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1