9.8

CVE-2026-92066: Sandbox escape in the Profile Backup component

Analyzed
AliasesUBUNTU-CVE-2026-92066
Published 15-09-2026Last modified 21-09-2026

Vulnerability summary

CVE-2026-92066 is a critical (CVSS 9.8) Protection Mechanism Failure vulnerability in mozilla firefox. EPSS estimates a 0.55% chance of exploitation in the next 30 days, higher than 45.3% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.8/10
010
Critical · v3.1 (CVE.org)
EPSS score
0.55%
0%100%
Low · +0.23 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 1 · Related 1
OPENSUSE-SU-2026:11826-1

Timeline

  1. 15-09-2026
    PublishedVulnerability first disclosed.
  2. 21-09-2026
    Last modifiedVulnerability information updated.

Description

Sandbox escape in the Profile Backup component. This vulnerability was fixed in Firefox 156 and Thunderbird 156.

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.55%

Chance of exploitation in the next 30 days

Percentile

45%

Versus all other CVEs

30-day change

Increase +0.23 pp

From 0.32% on 22-09-2026

22-09-202622-10-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Ubuntu8 products
  • mozjs102All versions (No fix recorded)
  • mozjs115All versions (No fix recorded)
  • mozjs38All versions (No fix recorded)
  • mozjs52All versions (No fix recorded)
  • mozjs68All versions (No fix recorded)
Mozilla2 products

2 vendors · 10 products

References

6 links