high
8.8
CWE
416
EPSS
0.106%
Advisory Published
CVE Published
Updated

CVE-2023-6859: Use After Free

First published: Tue Dec 19 2023(Updated: )

A use-after-free condition affected TLS socket creation when under memory pressure.

Credit: security@mozilla.org

Affected SoftwareAffected VersionHow to fix
redhat/firefox<115.6
115.6
redhat/thunderbird<115.6
115.6
debian/firefox
135.0.1-1
debian/firefox-esr
115.14.0esr-1~deb11u1
128.7.0esr-1~deb11u1
128.5.0esr-1~deb12u1
128.7.0esr-1~deb12u1
128.7.0esr-1
debian/thunderbird
1:115.12.0-1~deb11u1
1:128.7.0esr-1~deb11u1
1:128.5.0esr-1~deb12u1
1:128.7.0esr-1~deb12u1
1:128.7.0esr-1
Thunderbird<115.6
115.6
Firefox<121.0
Firefox ESR<115.6
Thunderbird<115.6
Debian=10.0
Debian=11.0
Debian=12.0
Firefox<121
121
Firefox ESR<115.6
115.6

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Reference Links

Parent vulnerabilities

(Appears in the following advisories)

Peer vulnerabilities

(Found alongside the following vulnerabilities)

Frequently Asked Questions

  • What is the severity of CVE-2023-6859?

    CVE-2023-6859 has been classified as a high severity vulnerability due to its potential to allow an attacker to exploit a use-after-free condition.

  • How do I fix CVE-2023-6859?

    To fix CVE-2023-6859, update Mozilla Firefox or Thunderbird to version 115.6 or later.

  • What software is affected by CVE-2023-6859?

    CVE-2023-6859 affects Mozilla Firefox ESR and Thunderbird versions prior to 115.6, as well as certain versions of Firefox up to 121.

  • What does a use-after-free vulnerability like CVE-2023-6859 entail?

    A use-after-free vulnerability like CVE-2023-6859 occurs when a program continues to use a pointer after the memory it points to has been freed, leading to potential memory corruption.

  • Can CVE-2023-6859 be exploited remotely?

    Yes, CVE-2023-6859 can potentially be exploited remotely if a user is misled into loading a malicious site that triggers the vulnerability.

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