High severity · published Apr 21, 2026
CVE-2026-6752
Incorrect boundary conditions in the WebRTC component
7.3
CVSS
0.3%
EPSS
No
On KEV
Description
Incorrect boundary conditions in the WebRTC component. This vulnerability was fixed in Firefox 150, Firefox ESR 115.35, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 23% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FI
Firefox · Mozilla
before 115.35.0; before 150.0; 140.0 before 140.10.0 · source: NVD
TH
Thunderbird · Mozilla
140.0 before 140.10.0 · source: NVD
RH
Red Hat Enterprise Linux 10 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 10.0 Extended Update Support · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 6 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 7 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 7 Extended Lifecycle Support · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 8 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 8.6 Telecommunications Update Service · Red Hat
All versions, or not specified · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-6752
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-6752
Permissions Required
https://bugzilla.mozilla.org/show_bug.cgi?id=2027499
Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-30/
Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-31/
Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-32/
Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-33/
Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-34/
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