CVE-2026-12327: Vulnerability in Mozilla Firefox
Memory safety vulnerabilities were identified in Mozilla Firefox ESR 140.11, Firefox 151, and Thunderbird 151. These bugs showed evidence of memory corruption and could potentially be exploited to execute arbitrary code. The issues were addressed and fixed in Firefox 152 and Firefox ESR 140.12. The vulnerabilities include a range of memory safety bugs with impacts assessed from moderate to high severity. No known exploits in the wild have been reported at this time.
AI Analysis
Technical Summary
CVE-2026-12327 concerns multiple memory safety bugs present in Firefox ESR 140.11, Thunderbird ESR 140.11, Firefox 151, and Thunderbird 151. These bugs exhibited evidence of memory corruption, which could have allowed attackers to execute arbitrary code with sufficient effort. Mozilla fixed these vulnerabilities in Firefox 152 and Firefox ESR 140.12. The vendor advisories detail numerous related memory safety issues fixed in these versions, with impacts ranging from low to high severity. The vulnerabilities affect both standard and ESR versions of Firefox and Thunderbird. No confirmed exploitation in the wild has been reported.
Potential Impact
The vulnerabilities could lead to arbitrary code execution due to memory corruption. This represents a significant security risk, potentially allowing attackers to compromise affected systems. The impact severity ranges from moderate to high depending on the specific bug. No active exploitation has been observed, but the potential for exploitation exists if the vulnerabilities are not remediated.
Mitigation Recommendations
Mozilla has released official fixes for these vulnerabilities in Firefox 152 and Firefox ESR 140.12. Users and administrators should update affected Firefox and Thunderbird installations to these versions or later to mitigate the risk. Since this is not a cloud service, patching the client software is required. Patch status is confirmed by the vendor advisories linked. No additional mitigation steps are indicated beyond applying these updates.
CVE-2026-12327: Vulnerability in Mozilla Firefox
Description
Memory safety vulnerabilities were identified in Mozilla Firefox ESR 140.11, Firefox 151, and Thunderbird 151. These bugs showed evidence of memory corruption and could potentially be exploited to execute arbitrary code. The issues were addressed and fixed in Firefox 152 and Firefox ESR 140.12. The vulnerabilities include a range of memory safety bugs with impacts assessed from moderate to high severity. No known exploits in the wild have been reported at this time.
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-12327 concerns multiple memory safety bugs present in Firefox ESR 140.11, Thunderbird ESR 140.11, Firefox 151, and Thunderbird 151. These bugs exhibited evidence of memory corruption, which could have allowed attackers to execute arbitrary code with sufficient effort. Mozilla fixed these vulnerabilities in Firefox 152 and Firefox ESR 140.12. The vendor advisories detail numerous related memory safety issues fixed in these versions, with impacts ranging from low to high severity. The vulnerabilities affect both standard and ESR versions of Firefox and Thunderbird. No confirmed exploitation in the wild has been reported.
Potential Impact
The vulnerabilities could lead to arbitrary code execution due to memory corruption. This represents a significant security risk, potentially allowing attackers to compromise affected systems. The impact severity ranges from moderate to high depending on the specific bug. No active exploitation has been observed, but the potential for exploitation exists if the vulnerabilities are not remediated.
Mitigation Recommendations
Mozilla has released official fixes for these vulnerabilities in Firefox 152 and Firefox ESR 140.12. Users and administrators should update affected Firefox and Thunderbird installations to these versions or later to mitigate the risk. Since this is not a cloud service, patching the client software is required. Patch status is confirmed by the vendor advisories linked. No additional mitigation steps are indicated beyond applying these updates.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-06-15T15:08:22.115Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-57/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-58/","vendor":"Mozilla"}]
Threat ID: 6a314c830b89be6888b4cde7
Added to database: 6/16/2026, 1:15:47 PM
Last enriched: 6/16/2026, 1:31:34 PM
Last updated: 6/16/2026, 6:35:35 PM
Views: 3
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