Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a5352debbd465a1…

MALICIOUS

PDF

91.2 KB Created: 2021-06-26 03:14:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 708e1d4ae3a6b1d5d96a80aa26ffaeda SHA-1: c30c753f61667c0448d3feb01bc50c27d9556cef SHA-256: 4a5352debbd465a1180cdb96513f7761da24874c6487584963f54d6134ad4b52
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document, potentially leveraging embedded JavaScript for redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://infrive.ru/uplcv?utm_term=file+manager+apk+root
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/617n11gcjshsbhsdosper2njde/nafajubewuwibazekujavojaw.pdf
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093aeac244e8---ramiw.pdf
    • https://blackknowledge.com/wp-content/plugins/super-forms/uploads/php/files/ae046a3790dbb58797efbe8d9a943602/tuzevutokorovamifolig.pdf
    • http://tremonttemplemacon.com/clients/862779/File/nevakoreguvobodeditev.pdf
    • http://md-servicios.com/userfiles/file/xujagosavapixosipevu.pdf
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/160b47446ec3dc---82707991162.pdf
    • http://www.segurosfacility.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609892b3c2001---40730483850.pdf
    • http://tamker.hu/userfiles/file/janube.pdf
    • https://bandotrading.com/uploads/file/takufamale.pdf
    • https://webtraffic.ch/wp-content/plugins/super-forms/uploads/php/files/nkhcnljp7o06qaluhvlhr7bk9d/2518660482.pdf
    • http://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b69fb173391---46199523997.pdf
    • http://celcg.pl/uploaded/file/xoputowuxaregi.pdf
    • https://weeb.nu/userfiles/file/57626695959.pdf
    • http://gianphoiduyloimodel.com/Images_upload/files/kobadotimudafivunoz.pdf
    • https://ferado.vn/userfiles/file/89662475094.pdf
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160837efd38922---25510162494.pdf
    • http://picassogift.com/Uploadfiles/files/67574328497.pdf
    • https://reflexlighting.com/wp-content/plugins/super-forms/uploads/php/files/395c5b4a4a7604cb2e1ab61600ab612c/63608451864.pdf
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/08c76ebed98da57491216faa3afe784d/28600944943.pdf
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607da2cdae0ec---57917164488.pdf
    • https://macleanpinesdrivingschool.com.au/wp-content/plugins/super-forms/uploads/php/files/dc9d69243c2a3a0187cd7596b8ec9316/22952815240.pdf
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e6fd.bin
1a39217fd672fe92429927fadb1da99c9867b727c75961d7ed736851ec06d027
pdf-font-stream PDF embedded font (sfnt) at offset 0xE6FD 10496 bytes
font_01_sfnt_off0000febc.bin
43c4896f9eb03187a6c5ed92a42f92c3e99a168f9e9d715879ddabadf163a4be
pdf-font-stream PDF embedded font (sfnt) at offset 0xFEBC 16216 bytes
font_02_sfnt_off0001149d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1149D 16792 bytes
font_03_sfnt_off00012caf.bin
380180833bbbfebfec7db9bfda745f8250574fc018845edebbd230dd7e9fbe2a
pdf-font-stream PDF embedded font (sfnt) at offset 0x12CAF 19164 bytes