high
8.8
CWE
119 787
EPSS
0.105%
Advisory Published
CVE Published
Updated

CVE-2023-6858: Buffer Overflow

First published: Tue Dec 19 2023(Updated: )

Firefox was susceptible to a heap buffer overflow in `nsTextFragment` due to insufficient OOM handling. External Reference: <a href="https://www.mozilla.org/en-US/security/advisories/mfsa2023-54/#CVE-2023-6858">https://www.mozilla.org/en-US/security/advisories/mfsa2023-54/#CVE-2023-6858</a>

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-2023-6858?

    CVE-2023-6858 is a critical vulnerability due to a heap buffer overflow in Firefox.

  • How do I fix CVE-2023-6858?

    To fix CVE-2023-6858, upgrade Firefox or Thunderbird to version 115.6 or later.

  • Which versions of Firefox are affected by CVE-2023-6858?

    CVE-2023-6858 affects Firefox versions prior to 115.6.

  • Is CVE-2023-6858 applicable to Thunderbird as well?

    Yes, CVE-2023-6858 also affects Thunderbird prior to version 115.6.

  • What kind of impact does CVE-2023-6858 have if exploited?

    If exploited, CVE-2023-6858 could allow remote attackers to execute arbitrary code.

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