CVE-2021-23975: mozilla firefox Missing Authorization
CVSS: 6.5v3.1MediumModified
AliasesUBUNTU-CVE-2021-23975
Published 26-02-2021Last modified 03-08-2024
Vulnerability summary
CVE-2021-23975 is a medium (CVSS 6.5) Missing Authorization vulnerability in mozilla firefox. EPSS estimates a 1.01% chance of exploitation in the next 30 days, higher than 62.6% of scored vulnerabilities.
CVSS score
6.5/10
010
Medium · v3.1 (NVD)EPSS score
1.01%
0%100%
Low · 0.00 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Advisory lineage
Upstream 0 · Downstream 3 · Related 3Timeline
- 26-02-2021PublishedVulnerability first disclosed.
- 03-08-2024Last modifiedVulnerability information updated.
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.
CVSS metrics
3 scores · 2 sources · 2 versionsMedium 6.5Preferred score · NVD (NIST)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:NSourcesAll 2 agree
- OSV · UbuntuEcosystem advisory · calculated6.5MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
Medium 4.3Preferred score · NVD (NIST)
AV:N/AC:M/Au:N/C:N/I:P/A:NSourcesSingle source
EPSS trend
Probability
1.01%
Chance of exploitation in the next 30 days
Percentile
63%
Versus all other CVEs
30-day change
0.00 pp
From 1.02% on 19-09-2026
19-09-202619-10-2026
EPSS score1.01%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Ubuntu5 products
- firefox< 86.0+build3-0ubuntu0.16.04.1 | < 86.0+build3-0ubuntu0.18.04.1 | < 86.0+build3-0ubuntu0.20.04.1
- mozjs38All versions (No fix recorded)
- mozjs52All versions (No fix recorded)
- mozjs68All versions (No fix recorded)
- mozjs78All versions (No fix recorded)
Mozilla1 product
- firefox< 86 | < 86.0
2 vendors · 6 products
References
7 links- bugzilla.mozilla.org/show_bug.cgi?id=1685145X Refsource MISCREPORTIssue TrackingPermissions RequiredVendor Advisory