6.5

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.

Overall risk
26/100
0100
Medium · default modelHow is this calculated?
CVSS score
6.5/10
010
Medium · v3.1 (NVD)
EPSS score
1.01%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 3 · Related 3

Timeline

  1. 26-02-2021
    PublishedVulnerability first disclosed.
  2. 03-08-2024
    Last 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 versions

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 score
1.01%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected 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

2 vendors · 6 products

References

7 links