CVE-2025-0242

Memory safety bugs fixed in Firefox 134, Thunderbird 134, Firefox ESR 115.19, Firefox ESR 128.6, Thunderbird 115.19, and Thunderbird 128.6

MEDIUM
6.5
CVSS Score
Published: January 7, 2025 at 04:07 PM UTC
Updated: October 5, 2026 at 03:10 PM UTC
2 products affected across 1 vendorFirefoxThunderbird

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Severity
MEDIUM6.5
Exploit prediction
EPSS 15%
SSVC
No known exploit

Description

Memory safety bugs present in Firefox 133, Thunderbird 133, Firefox ESR 115.18, Firefox ESR 128.5, Thunderbird 115.18, and Thunderbird 128.5. 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 < 134, Firefox ESR < 128.6, Firefox ESR < 115.19, Thunderbird < 134, and Thunderbird < 128.6.

Affected

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

v ≤ 115.19.0v < 134.0116.0 ≤ v < 128.6.0
Vendor states this is fixed in 115.19 (unaffected)
Vendor states this is fixed in 128.6 (unaffected)
Affected range stops below 128.6.0, so it looks safe — our inference, not a vendor statement
Vendor states this is fixed in 134 (unaffected)
Affected range stops below 134.0, so it looks safe — our inference, not a vendor statement
v < 128.6.0129.0 ≤ v < 134.0
Vendor states this is fixed in 128.6 (unaffected)
Affected range stops below 128.6.0, so it looks safe — our inference, not a vendor statement
Vendor states this is fixed in 134 (unaffected)
Affected range stops below 134.0, so it looks safe — our inference, not a vendor statement

SSVC — Action Prioritization

SSVCNo known exploitNot automatableTotal impact

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

CVSS

6.5MEDIUMCISA-ADP
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-787

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