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CVE-2021-23975
The developer page about:memory has a Measure function for exploring what object types the browser has allocated and their sizes. When…
Medium6.5EPSS 1.0%
- Published
- Updated
- Reserved
- Assigned by
- mozilla
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.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.1 | Medium6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N |
- EPSS (exploitation in 30 days)
- 1.0% · top 37% of all CVEs (6 Nov 2026)
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The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.5.
Weakness
- about:memory Measure function caused an incorrect pointer operation
- CWE-862 (opens in a new tab)All about CWE-862 and its CVEs
Affected products
References (3)
- https://www.mozilla.org/security/advisories/mfsa2021-07/ (opens in a new tab)x_refsource_MISCx_transferred
- https://bugzilla.mozilla.org/show_bug.cgi?id=1685145 (opens in a new tab)x_refsource_MISCx_transferred
- GLSA-202104-10 (opens in a new tab)vendor-advisoryx_refsource_GENTOOx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2021-23975)Record last updated .