Malicious PDF — malware analysis report

Static analysis result for SHA-256 aacbcd82d86d0f48…

MALICIOUS

PDF

85.2 KB Created: 2021-08-05 03:19:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: f98e4cd1d97e17397f0a59e1b23071d0 SHA-1: ae310270400c9dba24f0d6021280ebec003c2fac SHA-256: aacbcd82d86d0f4894db1c95fb483381c63368cae1ceb11588d35240101261e1
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs, several of which point to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and unreadable, providing no direct content clues, but the heuristic firings and URL analysis are sufficient to determine its nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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 http://loaamtran.vn/files/usersfiles/files/gomedazopa.pdf In PDF document text
    • http://www.hermosabeachbungalows.com/userfiles/files/zutela.pdfIn PDF document text
    • https://dprkoreatour.com/uploads/files/kerobamovugasinereku.pdfIn PDF document text
    • http://angarakshaksecurity.com/userfiles/file/kejedugaduwolekirik.pdfIn PDF document text
    • https://mattweidnerlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f387648556---17471996258.pdfIn PDF document text
    • https://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/6kq2e9jknht040grmhvt9h5df0/16315245355.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/43794052261.pdfIn PDF document text
    • http://sva-jeanroze.com/xmedia/file/mugufur.pdfIn PDF document text
    • http://s8radziejowice-paszkow.pl/userfiles/file/33515326668.pdfIn PDF document text
    • https://yziact.fr/wp-content/plugins/super-forms/uploads/php/files/itki2kvic97ekq91f6ulbia8hv/gogujutopetokawazagufuzi.pdfIn PDF document text
    • http://absolutelyneon.com/userfiles/file/wekupamodazapobowi.pdfIn PDF document text
    • http://aire-limpio.com/img/editor/file/ruzogurovebikapulisus.pdfIn PDF document text
    • http://ahkjt.com/upfile/file/3296096884.pdfIn PDF document text
    • http://acecaalcoy.com/userfiles/file/nurabinipeburelejixu.pdfIn PDF document text
    • http://carsongrad75.com/clients/3/35/35717660c32d3dd9b0ffde8f33a19d23/File/46335204009.pdfIn PDF document text
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/9888a174c92ddd85e8771917c37ae554/58536094983.pdfIn PDF document text
    • https://bestofbucerias.com/upload/file/42233361247.pdfIn PDF document text
    • http://herningbadintra.dk/app/webroot/upload/files/lupazebujukunawelevim.pdfIn PDF document text
    • http://maidnheaven.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d453e624f8---kunug.pdfIn PDF document text
    • https://alternatifhirdavat.com/upload/ckfinder/files/buranuzowa.pdfIn PDF document text
    • http://debsluxe.com/clients/1/17/174397649ed9f07baa8f9d9f48c72a4d/File/lobewojezusenijokuzevegi.pdfIn PDF document text
    • https://oncetrabzon.com/resimler/files/fasitovekawanexotoba.pdfIn PDF document text
    • http://jan-fotografie.nl/upload/files/kopesega.pdfIn PDF document text
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a09a308c35---55158346024.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=expressing+agreement+and+disagreement+exercises+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_off0000e5a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5A3 10880 bytes
SHA-256: 1ebc290012cbf5918447543572d4ef8761ac03655a990909cfe48fb5c15a75ea
font_01_sfnt_off0000fe9c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE9C 18292 bytes
SHA-256: 7d92c9f7a69b7d2bc7267c420c1c26ee07306a37df09975a53925de84e47ea74
font_02_sfnt_off00012e51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E51 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1