CVE-2025-0239 (GCVE-0-2025-0239)

Vulnerability from cvelistv5 – Published: 2025-01-07 16:07 – Updated: 2026-04-13 14:30
VLAI
Title
Alt-Svc ALPN validation failure when redirected
Summary
When using Alt-Svc, ALPN did not properly validate certificates when the original server is redirecting to an insecure site. This vulnerability was fixed in Firefox 134, Firefox ESR 128.6, Thunderbird 134, and Thunderbird 128.6.
Severity
4 (Medium)
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
CWE
  • CWE-295 - Improper Certificate Validation
Assigner
References
Impacted products
Vendor Product Version
Mozilla Firefox Unaffected: 128.6 , ≤ 128.* (rpm)
Unaffected: 134 , ≤ * (rpm)
Create a notification for this product.
Mozilla Thunderbird Unaffected: 128.6 , ≤ 128.* (rpm)
Unaffected: 134 , ≤ * (rpm)
Create a notification for this product.
Credits
Paul Gerste
Show details on NVD website
To clipboard 

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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.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • 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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