Memory safety bugs fixed in Firefox 136 and Thunderbird 136
Summary
| CVE | CVE-2025-1943 |
|---|---|
| State | PUBLISHED |
| Assigner | mozilla |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2025-03-04 14:15:39 UTC |
| Updated | 2026-04-13 15:16:54 UTC |
| Description | Memory safety bugs present in Firefox 135 and Thunderbird 135. 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. This vulnerability was fixed in Firefox 136 and Thunderbird 136. |
Risk And Classification
Primary CVSS: v3.1 8.2 HIGH from ADP
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
EPSS: 0.003630000 probability, percentile 0.583890000 (date 2026-04-15)
Problem Types: CWE-122 | CWE-122 CWE-122 Heap-based Buffer Overflow
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | ADP | DECLARED | 8.2 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H |
| 3.1 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | Secondary | 8.2 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
NoneIntegrity
LowAvailability
HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
NVD Known Affected Configurations (CPE 2.3)
| Type | Vendor | Product | Version | Update | Edition | Language |
|---|---|---|---|---|---|---|
| Application | Mozilla | Firefox | All | All | All | All |
| Application | Mozilla | Thunderbird | All | All | All | All |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Mozilla | Firefox | unaffected 136 * rpm | Not specified |
| CNA | Mozilla | Thunderbird | unaffected 136 * rpm | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| www.mozilla.org/security/advisories/mfsa2025-14 | [email protected] | www.mozilla.org | Vendor Advisory |
| www.mozilla.org/security/advisories/mfsa2025-17 | [email protected] | www.mozilla.org | Vendor Advisory |
| bugzilla.mozilla.org/buglist.cgi | [email protected] | bugzilla.mozilla.org | Broken Link |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: the Mozilla Fuzzing Team, Andrew McCreight, Sebastian Hengst, Randell Jesup (en)
There are currently no legacy QID mappings associated with this CVE.