Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5a25ddb5320ac6b…

MALICIOUS

PDF

91.9 KB Created: 2021-08-18 04:44:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: fa6bf4c8f302db9e1a44892fd5cf4eea SHA-1: 66a140ea60caee1de1514158527e0a92e16d37af SHA-256: c5a25ddb5320ac6b33759ed4e48332c62b92a47048413ed0fb8257f428c7e4be
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. It contains numerous embedded URLs, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users to malicious content. While no scripts were explicitly extracted, the nature of the embedded URLs and the 'link farm' heuristics strongly suggest an attempt to lure users to external malicious sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

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 http://tourhong.com/FileData/ckfinder/files/20210716_5552793FE55C5014.pdf In PDF document text
    • https://trouver-une-ssii.com/img/pics/files/98519557489.pdfIn PDF document text
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1608b0d932bc4d---29841819367.pdfIn PDF document text
    • https://pavaniautismschools.com/wp-content/plugins/super-forms/uploads/php/files/it71ftuec9ptpg1fcc9kbkgamv/xazomevato.pdfIn PDF document text
    • https://aimara-bg.com/userfiles/file/76713788416.pdfIn PDF document text
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/160d42f7a6c292---tumitivajum.pdfIn PDF document text
    • https://louvre.lv/res/wysiwyg/file/xigekefulage.pdfIn PDF document text
    • http://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607039712744b---24328419366.pdfIn PDF document text
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/80aae145f9086a08b4554066521e17b1/72065950180.pdfIn PDF document text
    • https://afanasyev-design.ru/wp-content/plugins/super-forms/uploads/php/files/89a4d43aebf7331b72a84b6f91285711/94676901500.pdfIn PDF document text
    • https://egyediajandekotletek.hu/mvc/userfiles/file/26657017654.pdfIn PDF document text
    • https://mediabandit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ff2a8c80249---91940629885.pdfIn PDF document text
    • https://ecole-anglais.com/upload/files/vuvadulixepilazavavov.pdfIn PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608a5870ba326---numipeweguvujubonaxuka.pdfIn PDF document text
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c1bfe6ac2a6---41109517652.pdfIn PDF document text
    • http://kochamsushi.pl/UserFiles/file/boriguzuxidajomut.pdfIn PDF document text
    • http://iglozawiercie.pl/zdjecia/file/goxagiradametonoteg.pdfIn PDF document text
    • http://webinaris.org/ckfinder/userfiles/publics/files/zuwovezoluwuxovitawul.pdfIn PDF document text
    • http://bulongvungtau.com/media/ftp/file/zukivofimaxitagis.pdfIn PDF document text
    • http://andreevmag.com/wp-content/plugins/super-forms/uploads/php/files/7b83f5dcaaa2138d26466990a3805a9d/tewagujovamezumod.pdfIn PDF document text
    • http://ed-web.cz/userfilesfile/kibosubi.pdfIn PDF document text
    • http://serramentisiciliano.it/userfiles/files/benoninopavofetojebim.pdfIn PDF document text
    • https://dafelia.com/files/forakozegiwutogapusodofi.pdfIn PDF document text
    • https://www.keystonecare.co.uk/wp-content/plugins/super-forms/uploads/php/files/ad3a650c3ebe5cd0d27e621257b4f8e8/1030216526.pdfIn PDF document text
    • https://bkht.vn/userfiles/file/30087363004.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=how+to+reprogram+schlage+keypad+lockPDF 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_off00010238.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10238 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011a4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A4A 17072 bytes
SHA-256: 1b4a86f302be2fbe931037a21b52682c3e6ce708c7bea76adc60ff3b09545284
font_02_sfnt_off000146e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x146E3 11048 bytes
SHA-256: ff02a82376ebddebd0f7fd462d04f0f0d87f3e32afef0b9f5cb1b0f882dffda1