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Status published
Medium
CVE-2021-23975
The developer page about:memory has a Measure function for exploring...
Vulnerability Description
The developer page about:memory has a Measure function for exploring what object types the browser has allocated and their sizes. When this function was invoked we incorrectly called the sizeof function, instead of using the API method that checks for invalid pointers. This vulnerability affects Firefox < 86.
Impact Analysis
Refer to official advisory for detailed impact metrics.
Remediation
Ensure systems are updated to the latest vendor-supplied patch levels.
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Credits & Attribution
No credits recorded in the NVD database.
References
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CVE-2025-9183
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Affected Vendor
Mozilla
View all reports →Affected Software
Firefox
Vulnerable Versions:
< 86
Timeline
Official Publish:
February 26th, 2021
Last Modified:
August 3rd, 2024
Added to House:
July 21st, 2026
CVSS Vectors
V3:
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
Weaknesses (CWE)
No CWE data available
MITRE ATT&CK TTPs
No associated TTPs found for this vulnerability.