CVE-2026-100521

Cotonti through 1.0.0 Reflected XSS via search highlight parameter

Published Sep 26, 2026 CVSS 4.0 · 5.1 Medium EPSS < 1% KEV · Not listed
Description
Cotonti through 1.0.0 contains a reflected cross-site scripting vulnerability in the search plugin highlight parameter that performs no HTML or JavaScript escaping. Attackers can craft malicious links with injected JavaScript in the highlight parameter that executes in the browser of any visitor who opens the link, including administrators.

Analysis

AI-generated

Technical impact

Cotonti through version 1.0.0 contains a reflected cross‑site scripting vulnerability in its search plugin. The highlight parameter accepts unsanitized input, allowing attackers to embed malicious JavaScript that executes in a visitor’s browser when the link is opened. This flaw permits code execution under the context of the victim, potentially exposing session cookies, defacing content, or redirecting to phishing sites.

Affected Systems

All installations of Cotonti using the default search plugin up to and including version 1.0.0 are affected. The vulnerability is present in the plugin files "search.header.php" and "search.page.first.php", and affects any deployment that enables the highlight feature of the search module. Administrators or any user clicking the crafted link will trigger the flaw.

Risk and Exploitability

The CVSS score of 5.1 indicates a moderate severity, and the EPSS score is not available, so current exploitation probability is uncertain. The issue is not listed in the CISA KEV catalog, meaning no widely disclosed exploits are known. The attack vector is web‑based and requires only a crafted URL; no authentication or privileged access is needed. The exposure primarily threatens confidentiality and integrity in the scope of affected user sessions.

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

  • Update to the patched version of Cotonti that incorporates the fix from pull request 1908.
  • If an immediate upgrade is not possible, disable or remove the search plugin’s highlight parameter or enable the plugin to sanitize the highlight value before rendering.
  • If disabling is not feasible, modify the plugin files to escape the highlight input using a proper HTML escaping function before output.

Generated by OpenCVE AI on September 26, 2026 at 02:32 UTC.

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Cotonti cotonti
Cotonti siena
Vendors & Products Cotonti cotonti
Cotonti siena
Type Values Removed Values Added
Description Cotonti through 1.0.0 contains a reflected cross-site scripting vulnerability in the search plugin highlight parameter that performs no HTML or JavaScript escaping. Attackers can craft malicious links with injected JavaScript in the highlight parameter that executes in the browser of any visitor who opens the link, including administrators.
Title Cotonti through 1.0.0 Reflected XSS via search highlight parameter
First Time appeared Cotonti
Cotonti cotonti Siena
Weaknesses CWE-79
CPEs cpe:2.3:a:cotonti:cotonti_siena:*:*:*:*:*:*:*:*
Vendors & Products Cotonti
Cotonti cotonti Siena
References
Metrics cvssV3_1

{'score': 6.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N'}

cvssV4_0

{'score': 5.1, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N'}

Weaknesses
  • CWE-79

    Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Sources

Status
PUBLISHED
Assigner
VulnCheck
Published
Updated
Sep 29, 2026, 5:22 PM
Reserved
Sep 26, 2026, 12:48 AM
Status
Deferred
Published
Sep 26, 2026, 1:17 AM
Modified
Sep 29, 2026, 6:17 PM