ESB-2026.4407
PUBLISHED
CVSS 9.300000190734863 CRITICAL
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AUSCERT External Security Bulletin Redistribution
ESB-2026.4407
MFSA 2026-36 Security Vulnerabilities fixed in Firefox ESR 140.10.1
29 April 2026
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AUSCERT Security Bulletin Summary
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Product: Mozilla Firefox ESR
Publisher: Mozilla Foundation
Operating System: Windows
Linux
macOS
Resolution: Patch/Upgrade
CVE Names: CVE-2026-7323 CVE-2026-7320 CVE-2026-7321
CVE-2026-7322
Original Bulletin:
https://www.mozilla.org/en-US/security/advisories/mfsa2026-36/
Comment: CVSS (Max): 9.6* CVE-2026-7321 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H)
CVSS Source: CISA-ADP
Calculator: https://www.first.org/cvss/calculator/3.1#CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
* Not all CVSS available when published
EPSS (Max): None available when published
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Mozilla Foundation Security Advisory 2026-36
Security Vulnerabilities fixed in Firefox ESR 140.10.1
Announced: April 28, 2026
Impact: high
Products: Firefox ESR
Fixed in: Firefox ESR 140.10.1
# CVE-2026-7320: Information disclosure due to incorrect boundary conditions in
the Audio/Video component
Reporter: Xuehao Guo
Impact: high
References
o Bug 2027433
# CVE-2026-7321: Sandbox escape due to incorrect boundary conditions in the
WebRTC: Networking component
Reporter: Bugmon
Impact: moderate
References
o Bug 2029461
# CVE-2026-7322: Memory safety bugs fixed in Firefox ESR 115.35.1, Firefox ESR
140.10.1 and Firefox 150.0.1
Reporter: C.M.Chang, Christian Holler, Steve Fink and the Mozilla Fuzzing Team
Impact: critical
Description
Memory safety bugs present in Firefox ESR 115.35.0, Firefox ESR 140.10.0 and
Firefox 150.0.0. Some of these bugs showed evidence of memory corruption and we
presume that with enough effort some of these could have been exploited to run
arbitrary code.
References
o Memory safety bugs fixed in Firefox ESR 115.35.1, Firefox ESR 140.10.1 and
Firefox 150.0.1
# CVE-2026-7323: Memory safety bugs fixed in Firefox ESR 140.10.1 and Firefox
150.0.1
Reporter: Ryan Hunt, Steve Fink and the Mozilla Fuzzing Team
Impact: high
Description
Memory safety bugs present in Firefox ESR 140.10.0 and Firefox 150.0.0. Some of
these bugs showed evidence of memory corruption and we presume that with enough
effort some of these could have been exploited to run arbitrary code.
References
o Memory safety bugs fixed in Firefox ESR 140.10.1 and Firefox 150.0.1
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