high
8.8
CWE
119 787
EPSS
0.604%
Advisory Published
CVE Published
Updated

CVE-2023-6856: Buffer Overflow

First published: Tue Dec 19 2023(Updated: )

Last updated 24 July 2024

Credit: security@mozilla.org

Affected SoftwareAffected VersionHow to fix
redhat/firefox<115.6
115.6
redhat/thunderbird<115.6
115.6
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
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

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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-2023-6856?

    CVE-2023-6856 is classified as a critical vulnerability due to its potential to allow remote code execution and sandbox escape.

  • How do I fix CVE-2023-6856?

    To mitigate CVE-2023-6856, users should upgrade affected software to versions 115.6 or later for Thunderbird and Firefox, as well as 121 for newer Firefox versions.

  • Which software is affected by CVE-2023-6856?

    CVE-2023-6856 affects Mozilla Thunderbird and Mozilla Firefox, specifically versions prior to 115.6 and newer than 121.

  • What type of vulnerability is CVE-2023-6856?

    CVE-2023-6856 is a heap buffer overflow vulnerability that occurs in the WebGL DrawElementsInstanced method.

  • Can CVE-2023-6856 be exploited remotely?

    Yes, CVE-2023-6856 can be exploited remotely, potentially allowing an attacker to execute arbitrary code on a vulnerable system.

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