6.5

CVE-2021-23956: mozilla firefox

CVSS: 6.5v3.1MediumModified
AliasesUBUNTU-CVE-2021-23956
Published 26-02-2021Last modified 03-08-2024
Open JSON

Vulnerability summary

CVE-2021-23956 is a medium (CVSS 6.5) vulnerability in mozilla firefox. EPSS estimates a 0.99% chance of exploitation in the next 30 days, higher than 62% of scored vulnerabilities. 1 public exploit is recorded.

Overall risk
36/100
0100
Medium · default modelHow is this calculated?
CVSS score
6.5/10
010
Medium · v3.1 (NVD)
EPSS score
0.99%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1reference

Advisory lineage

Upstream 0 · Downstream 3 · Related 3
OPENSUSE-SU-2024:10600-1OPENSUSE-SU-2024:14572-1USN-4717-1

Timeline

  1. 26-02-2021
    PublishedVulnerability first disclosed.
  2. 03-08-2024
    Last modifiedVulnerability information updated.

Description

An ambiguous file picker design could have confused users who intended to select and upload a single file into uploading a whole directory. This was addressed by adding a new prompt. This vulnerability affects Firefox < 85.

CVSS metrics

3 scores · 2 sources · 2 versions

EPSS trend

Probability

0.99%

Chance of exploitation in the next 30 days

Percentile

62%

Versus all other CVEs

30-day change

0.00 pp

From 0.99% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.99%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

1 found
  • referenceUnverified

    Exploit Reference (bugzilla.mozilla.org)

    Maturity: unknown

Weaknesses

CWE · root cause

No weakness data has been published for this record.

Affected systems

Ubuntu5 products
  • firefox< 85.0+build1-0ubuntu0.16.04.1 | < 85.0+build1-0ubuntu0.18.04.1 | < 85.0+build1-0ubuntu0.20.04.1
  • 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

6 links