CVE-2023-6856
HIGH
8.8
CVSS Score
Published: December 19, 2023 at 01:38 PM UTC
Updated: June 17, 2026 at 06:51 AM UTC
4 products affected across 2 vendorsDebian LinuxFirefoxThunderbird
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Severity
HIGH8.8
Exploit prediction
EPSS 21%
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.
Affected
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
Debian Linux· Debiandrupal
95%v < 121
Affected range stops below 121, so it looks safe — our inference, not a vendor statement
Affected range stops below 121.0, so it looks safe — our inference, not a vendor statement
v < 115.6
Affected range stops below 115.6, so it looks safe — our inference, not a vendor statement
v < 115.6
Affected range stops below 115.6, so it looks safe — our inference, not a vendor statement
Remediation
No guide yetNo remediation guidance has been written for this CVE yet. What the record does show:
References (9)
Issue TrackingPermissions Required
Source: [email protected]
https://bugzilla.mozilla.org/show_bug.cgi?id=1843782Mailing ListThird Party Advisory
Source: [email protected]
https://lists.debian.org/debian-lts-announce/2023/12/msg00020.htmlMailing ListThird Party Advisory
Source: [email protected]
https://lists.debian.org/debian-lts-announce/2023/12/msg00021.htmlCVSS
- Attack Vector
- NETWORK
- Complexity
- LOW
- Privileges
- NONE
- User Interaction
- REQUIRED
- Scope
- UNCHANGED
- Confidentiality
- HIGH
- Integrity
- HIGH
- Availability
- HIGH
Vector?
Quick Info
StatusMODIFIED
CWE
CWE-787
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