CVE-2026-100523 (GCVE-0-2026-100523)

Vulnerability from cvelistv5 – Published: 2026-09-26 00:59 – Updated: 2026-09-26 00:59
VLAI
Title
Cotonti through 1.0.0 Open Redirect via message.php redirect parameter
Summary
Cotonti through 1.0.0 contains an open redirect vulnerability in message.php that base64-decodes the redirect parameter without domain validation. Unauthenticated attackers can craft malicious links with encoded external URLs to redirect users to arbitrary sites via meta refresh tags for phishing attacks.
Severity
5.1 (Medium)
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
6.1 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
CWE
  • CWE-601 - URL Redirection to Untrusted Site ('Open Redirect')
Assigner
References
Impacted products
Vendor Product Version CPE status
Cotonti Cotonti Affected: 0 , ≤ 1.0.0 (custom)
    cpe:2.3:a:cotonti:cotonti_siena:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-09-25 00:00
Credits
Harsh Raj Singhania
Show details on NVD website
To clipboard 

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}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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