CVE-2026-92034: Site isolation issue in the Graphics component
Analyzed
AliasesUBUNTU-CVE-2026-92034
Published 15-09-2026Last modified 21-09-2026
Vulnerability summary
CVE-2026-92034 is a critical (CVSS 9.1) Origin Validation Error vulnerability in mozilla firefox. EPSS estimates a 0.27% chance of exploitation in the next 30 days, higher than 18.8% of scored vulnerabilities.
CVSS score
9.1/10
010
Critical · v3.1 (CVE.org)EPSS score
0.27%
0%100%
Low · +0.06 pp in 30 daysKEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded
Advisory lineage
Upstream 0 · Downstream 1 · Related 1Timeline
- 15-09-2026PublishedVulnerability first disclosed.
- 21-09-2026Last modifiedVulnerability information updated.
Description
Site isolation issue in the Graphics component. This vulnerability was fixed in Firefox 156 and Thunderbird 156.
CVSS metrics
3 scores · 3 sources · 1 versionCritical 9.1Preferred score · CVE.org (CNA)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:HSourcesAll 3 agree
- OSV · UbuntuEcosystem advisory · calculated9.1CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
- NVDNIST9.1CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
EPSS trend
Probability
0.27%
Chance of exploitation in the next 30 days
Percentile
19%
Versus all other CVEs
30-day change
Increase +0.06 pp
From 0.21% on 22-09-2026
22-09-202622-10-2026
Known exploited
Compare KEV catalogsNot in the CISA KEV catalog.
Not in the ENISA CNW catalog.
Not in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected 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
- firefox< 156.0.0
- thunderbird< 156.0
2 vendors · 10 products
References
6 links- bugzilla.mozilla.org/show_bug.cgi?id=2060295Permissions Required
- www.mozilla.org/security/advisories/mfsa2026-90/Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-94/Vendor Advisory