Malicious PDF — malware analysis report

Static analysis result for SHA-256 5339b21b1210db6f…

MALICIOUS

PDF

78.3 KB Created: 2021-07-16 18:19:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6ba95ada23d4413a44643fccfdf6f5e0 SHA-1: 554ae5f8aec980cd3522bf45c74b2409a0486624 SHA-256: 5339b21b1210db6fee7a484fefffe9b083c246daed910620cd91dc94e4aebbc3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple compromised websites and potentially disposable hosting, suggesting a phishing or SEO poisoning attack. While no scripts were extracted, the embedded URLs and the nature of the link farm indicate an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://amatnieks.com/pictures/image/95785458374.pdf
    • http://alituncer.com/userfiles/file/91287387379.pdf
    • http://www.festivalmarrakech.info/wp-content/plugins/formcraft/file-upload/server/content/files/160e21173ba43e---73868841644.pdf
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a100d61bcb7---55166835685.pdf
    • http://goodmix-psc.com/userfiles/files/jugenavemodisas.pdf
    • https://apoiotelecom.com/imagens/img_fckeditor/file/75412344642.pdf
    • http://best-infosystems.com/userfiles/file/xegivowifo.pdf
    • http://gaongonmaiphuong.vn/webroot/img/files/33583858577.pdf
    • https://electrabicycles.pl/app/webroot/uploads/file/16213633232947.pdf
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/16078dc48aa7a6---63296585393.pdf
    • https://kaptenhoki.net/contents//files/1372878202.pdf
    • http://paillasse.hu/userfiles/file/duwolarego.pdf
    • https://portsidestrategies.com/wp-content/plugins/super-forms/uploads/php/files/2801bfc24db31ddb889bd65295caff72/jobofotagolokate.pdf
    • http://juentai.com/userfiles/files/54048427135.pdf
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cbac206c813---nokogoxiwelep.pdf
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/0fb8785e2f776b4c3be67e7e8b316ac4/47271240332.pdf
    • https://capitaleny.com/wp-content/plugins/super-forms/uploads/php/files/f6014d0f4080ea41945f87e82c9c247a/kojijofenanezix.pdf
    • https://autoandtruckrepair.net/nbloom/fckuploads/file/zesinusopisafipivefof.pdf
    • http://broadgatecapital.com/userfiles/file/porige.pdf
    • http://cesishotel.lv/res/wysiwyg/file/63323956655.pdf
    • http://saamfactory.com/wp-content/plugins/super-forms/uploads/php/files/3b0bb7ced1eba13497b62658ab3334c5/kanefemiboduwu.pdf
    • http://boulderdivorcelaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c0a0c35b95---toxirifezexiwopogatiti.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=nothing+is+impossible+quotes+bible
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cd54.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCD54 16792 bytes
font_01_sfnt_off0000e566.bin
7b3b6f52ec41bab92afe1f4efc7af9a6f41e63d0ae6528f96334a704509e3beb
pdf-font-stream PDF embedded font (sfnt) at offset 0xE566 17144 bytes
font_02_sfnt_off0001124b.bin
022b1854851cdf4c0bb9d7a8c43ffe9010ad79ed3f985bf659513e5c67b8e479
pdf-font-stream PDF embedded font (sfnt) at offset 0x1124B 10800 bytes