CVE-2026-12298

🔶 medium

Summary

Memory safety bug fixed in Thunderbird 152. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.

CVSS Score

5.4

Medium

EPSS Score

0.2

Exploit Probability

Published Date

2026-06-16

First Seen: 2026-06-17

📊 Relative Risk Intelligence

This CVE is Lower Risk - more severe than 22.8% of all 328,009 vulnerabilities in our database.

#253,218

Below average severity

Severity Percentile

🎯 CISA SSVC Assessment Updated: Jun 16, 2026

🔍 Exploitation Status

None

No known exploits

⚙️ Automatable

Requires human interaction

💥 Technical Impact

Partial

Limited system impact

🏆 Discovered By

Haruka Yamazaki

SSVC data provided by CISA

Last Modified 2026-06-16

Source NVD 🔗

CVSS Vector 3.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N

CWE IDs (Weakness Types)

CWE-125 CWE-416 CWE-787

📦 Affected Products 4

Vendor	Product	Status	Affected Versions
mozilla	firefox	Affected	> 140.0 < 140.12.0
mozilla	firefox	Affected	< 152.0
mozilla	thunderbird	Affected	> 140.0 < 140.12.0
mozilla	thunderbird	Affected	< 152.0.0

🔗 References 5

https://bugzilla.mozilla.org/show_bug.cgi?id=2041981

Permissions Required

https://www.mozilla.org/security/advisories/mfsa2026...

Vendor Advisory

https://www.mozilla.org/security/advisories/mfsa2026...

Vendor Advisory

https://www.mozilla.org/security/advisories/mfsa2026...

Vendor Advisory

https://www.mozilla.org/security/advisories/mfsa2026...

Vendor Advisory

🔗 Related CVEs 6

CVE ID	Severity	CVSS	EPSS	Summary	Published
CVE-2026-12289	⚠️ high	8.8	0.3	Privilege escalation in the Graphics: WebRender component. This vulnerability was fixed in Firefox 152, Firefox ESR 140....	2026-06-16
CVE-2026-12299	🔶 medium	5.4	0.2	JIT miscompilation in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, F...	2026-06-16
CVE-2026-12303	🔶 medium	4.3	0.2	Information disclosure due to incorrect boundary conditions in the Graphics: WebGPU component. This vulnerability was fi...	2026-06-16
CVE-2026-12311	🔶 medium	4.7	0.2	Information disclosure, sandbox escape in the Security: Process Sandboxing component. This vulnerability was fixed in Fi...	2026-06-16
CVE-2026-12313	🔶 medium	4.7	0.2	Information disclosure, sandbox escape in the Security: Process Sandboxing component. This vulnerability was fixed in Fi...	2026-06-16
CVE-2026-12319	🔶 medium	6.5	0.2	Denial-of-service in the Audio/Video: Playback component. This vulnerability was fixed in Firefox 152 and Thunderbird 15...	2026-06-16

These CVEs affect the same products