CVE-2025-0239
First published: Tue Jan 07 2025(Updated: )
Last updated 9 January 2025
Credit: security@mozilla.org security@mozilla.org
| Affected Software | Affected Version | How to fix |
|---|---|---|
| debian/firefox | 134.0-1 | |
| debian/firefox-esr | <=115.14.0esr-1~deb11u1<=128.5.0esr-1~deb11u1<=128.3.1esr-1~deb12u1<=128.5.0esr-1 | 128.6.0esr-1~deb12u1 128.6.0esr-1 |
| Mozilla Firefox ESR | <128.6 | 128.6 |
| Mozilla Firefox | <134 | 134 |
| Mozilla Thunderbird | <134 | 134 |
| Mozilla Thunderbird | <128.6 | 128.6 |
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Reference Links
- https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2025-0239
- https://nvd.nist.gov/vuln/detail/CVE-2025-0239
- https://launchpad.net/bugs/cve/CVE-2025-0239
- https://security-tracker.debian.org/tracker/CVE-2025-0239
- https://ubuntu.com/security/CVE-2025-0239
- https://www.mozilla.org/en-US/security/advisories/mfsa2025-01/#CVE-2025-0239
- https://www.mozilla.org/en-US/security/advisories/mfsa2025-02/#CVE-2025-0239
- https://bugzilla.mozilla.org/show_bug.cgi?id=1929156
- https://www.mozilla.org/security/advisories/mfsa2025-01/
- https://www.mozilla.org/security/advisories/mfsa2025-02/
- https://www.mozilla.org/en-US/security/advisories/mfsa2025-02/
- https://www.mozilla.org/en-US/security/advisories/mfsa2025-01/
- https://www.mozilla.org/security/advisories/mfsa2025-04/
- https://www.mozilla.org/security/advisories/mfsa2025-05/
- https://www.mozilla.org/en-US/security/advisories/mfsa2025-04/
- https://www.mozilla.org/en-US/security/advisories/mfsa2025-05/
- https://access.redhat.com/errata/RHSA-2025:0080
- https://access.redhat.com/errata/RHSA-2025:0133
- https://access.redhat.com/errata/RHSA-2025:0135
- https://access.redhat.com/errata/RHSA-2025:0134
- https://access.redhat.com/errata/RHSA-2025:0132
- https://access.redhat.com/errata/RHSA-2025:0136
- https://access.redhat.com/errata/RHSA-2025:0138
- https://access.redhat.com/errata/RHSA-2025:0137
- https://access.redhat.com/errata/RHSA-2025:0144
- https://access.redhat.com/errata/RHSA-2025:0162
- https://bugzilla.redhat.com/show_bug.cgi?id=2336170
Parent vulnerabilities
(Appears in the following advisories)
Peer vulnerabilities
(Found alongside the following vulnerabilities)
Frequently Asked Questions
What is the severity of CVE-2025-0239?
CVE-2025-0239 has been rated as a high severity vulnerability due to its impact on certificate validation during insecure redirects.
How do I fix CVE-2025-0239?
To fix CVE-2025-0239, update your Firefox or Thunderbird application to the latest version available, specifically version 134 or 128.6 for Firefox ESR.
Which versions of Firefox are affected by CVE-2025-0239?
CVE-2025-0239 affects Firefox versions prior to 134 and Firefox ESR versions prior to 128.6.
Is Thunderbird affected by CVE-2025-0239?
Yes, Thunderbird versions prior to 134 and 128.6 are affected by CVE-2025-0239.
What type of vulnerability is CVE-2025-0239?
CVE-2025-0239 is a security vulnerability related to improper certificate validation in Alt-Svc and ALPN.
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