CVE-2023-6856

Description

The WebGL `DrawElementsInstanced` method was susceptible to a heap buffer overflow when used on systems with the Mesa VM driver. This issue could allow an attacker to perform remote code execution and sandbox escape. This vulnerability affects Firefox ESR < 115.6, Thunderbird < 115.6, and Firefox < 121.

Category

8.8
CVSS
Severity: High
CVSS 3.1 •
EPSS 10.11% Top 10%
Vendor Advisory mozilla.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org
Affected: Mozilla Firefox ESR
Affected: Mozilla Thunderbird
Affected: Mozilla Firefox
Published at:
Updated at:

References

Link Tags
https://bugzilla.mozilla.org/show_bug.cgi?id=1843782 issue tracking permissions required
https://www.mozilla.org/security/advisories/mfsa2023-54/ vendor advisory
https://www.mozilla.org/security/advisories/mfsa2023-55/ vendor advisory
https://www.mozilla.org/security/advisories/mfsa2023-56/ vendor advisory
https://www.debian.org/security/2023/dsa-5581 third party advisory
https://www.debian.org/security/2023/dsa-5582 third party advisory
https://lists.debian.org/debian-lts-announce/2023/12/msg00020.html third party advisory mailing list
https://lists.debian.org/debian-lts-announce/2023/12/msg00021.html third party advisory mailing list
https://security.gentoo.org/glsa/202401-10 third party advisory

Frequently Asked Questions

What is the severity of CVE-2023-6856?
CVE-2023-6856 has been scored as a high severity vulnerability.
How to fix CVE-2023-6856?
To fix CVE-2023-6856, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2023-6856 being actively exploited in the wild?
It is possible that CVE-2023-6856 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~10% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-6856?
CVE-2023-6856 affects Mozilla Firefox ESR, Mozilla Thunderbird, Mozilla Firefox.
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