4.3

CVE-2021-29958: mozilla firefox Missing Authorization

CVSS: 4.3v3.1MediumModified
Published 24-06-2021Last modified 03-08-2024
Open JSON

Vulnerability summary

CVE-2021-29958 is a medium (CVSS 4.3) Missing Authorization vulnerability in mozilla firefox. EPSS estimates a 0.67% chance of exploitation in the next 30 days, higher than 51.1% of scored vulnerabilities.

Overall risk
17/100
0100
Low · default modelHow is this calculated?
CVSS score
4.3/10
010
Medium · v3.1 (NVD)
EPSS score
0.67%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 24-06-2021
    PublishedVulnerability first disclosed.
  2. 03-08-2024
    Last modifiedVulnerability information updated.

Description

When a download was initiated, the client did not check whether it was in normal or private browsing mode, which led to private mode cookies being shared in normal browsing mode. This vulnerability affects Firefox for iOS < 34.

CVSS metrics

2 scores · 1 source · 2 versions

EPSS trend

Probability

0.67%

Chance of exploitation in the next 30 days

Percentile

51%

Versus all other CVEs

30-day change

0.00 pp

From 0.67% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.67%

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

Mozilla2 products

1 vendor · 2 products

References

2 links