7.5

CVE-2021-38498: mozilla firefox Use After Free

CVSS: 7.5v3.1HighModified
AliasesUBUNTU-CVE-2021-38498
Published 03-11-2021Last modified 04-08-2024
Open JSON

Vulnerability summary

CVE-2021-38498 is a high (CVSS 7.5) Use After Free vulnerability in mozilla firefox. EPSS estimates a 1.47% chance of exploitation in the next 30 days, higher than 73.3% of scored vulnerabilities.

Overall risk
30/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.5/10
010
High · v3.1 (NVD)
EPSS score
1.47%
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 25 · Related 15
MGASA-2021-0469MGASA-2021-0478OPENSUSE-SU-2021:1367-1OPENSUSE-SU-2021:1635-1OPENSUSE-SU-2021:3331-1OPENSUSE-SU-2021:3451-1

Timeline

  1. 03-11-2021
    PublishedVulnerability first disclosed.
  2. 04-08-2024
    Last modifiedVulnerability information updated.

Description

During process shutdown, a document could have caused a use-after-free of a languages service object, leading to memory corruption and a potentially exploitable crash. This vulnerability affects Firefox < 93, Thunderbird < 91.2, and Firefox ESR < 91.2.

CVSS metrics

3 scores · 2 sources · 2 versions

EPSS trend

Probability

1.47%

Chance of exploitation in the next 30 days

Percentile

73%

Versus all other CVEs

30-day change

0.00 pp

From 1.47% on 19-09-2026

19-09-202619-10-2026
EPSS score
1.47%

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

Ubuntu6 products
  • firefox< 93.0+build1-0ubuntu0.18.04.1 | < 93.0+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)
Mozilla3 products

2 vendors · 9 products

References

10 links