CVE-2026-12303 Info Disclosure via WebGPU Boundary Conditions in Firefox
CVE-2026-12303 Published on June 16, 2026

Information disclosure due to incorrect boundary conditions in the Graphics: WebGPU component
Information disclosure due to incorrect boundary conditions in the Graphics: WebGPU component. This vulnerability was fixed in Firefox 152 and Thunderbird 152.

NVD

Vulnerability Analysis

CVE-2026-12303 can be exploited with network access, requires user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have a small impact on confidentiality, a small impact on integrity and availability.

Attack Vector:
NETWORK
Attack Complexity:
LOW
Privileges Required:
NONE
User Interaction:
REQUIRED
Scope:
UNCHANGED
Confidentiality Impact:
LOW
Integrity Impact:
NONE
Availability Impact:
NONE

Weakness Type

Out-of-bounds Read

The software reads data past the end, or before the beginning, of the intended buffer. Typically, this can allow attackers to read sensitive information from other memory locations or cause a crash. A crash can occur when the code reads a variable amount of data and assumes that a sentinel exists to stop the read operation, such as a NUL in a string. The expected sentinel might not be located in the out-of-bounds memory, causing excessive data to be read, leading to a segmentation fault or a buffer overflow. The software may modify an index or perform pointer arithmetic that references a memory location that is outside of the boundaries of the buffer. A subsequent read operation then produces undefined or unexpected results.


Products Associated with CVE-2026-12303

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Affected Versions

Mozilla Firefox: Mozilla Thunderbird:

Exploit Probability

EPSS
0.22%
Percentile
12.53%

EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.