CVE-2025-3034

Memory safety bugs fixed in Firefox 137 and Thunderbird 137

HIGH
8.1
CVSS Score
Published: April 1, 2025 at 12:29 PM UTC
Updated: September 30, 2026 at 06:10 PM UTC
2 products affected across 1 vendorFirefoxThunderbird

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Severity
HIGH8.1
Exploit prediction
EPSS 0.5%
SSVC
No known exploit

Description

Memory safety bugs present in Firefox 136 and Thunderbird 136. 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 affects Firefox < 137 and Thunderbird < 137.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 137.0
Vendor states this is fixed in 137 (unaffected)
Affected range stops below 137.0, so it looks safe — our inference, not a vendor statement
v < 137.0
Vendor states this is fixed in 137 (unaffected)
Affected range stops below 137.0, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

8.1HIGHCISA-ADP
Attack Vector
NETWORK
Complexity
HIGH
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-787

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