CVE-2024-9396

Severity: high (CVSS 8.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-10-01 · updated 2026-06-17
Weakness: CWE-119

Description

It is currently unknown if this issue is exploitable but a condition may arise where the structured clone of certain objects could lead to memory corruption. This vulnerability affects Firefox < 131, Firefox ESR < 128.3, Thunderbird < 128.3, and Thunderbird < 131.

Affected products

Mozilla Firefox: before 128.3.0; before 131.0 — fixed in 128.3.0, 131.0
Mozilla Thunderbird: before 128.3.0; from 129.0 before 131.0 — fixed in 128.3.0, 131.0

How to fix

Upgrade to a fixed version: Mozilla Firefox 128.3.0, 131.0; Mozilla Thunderbird 128.3.0, 131.0. Check the vendor advisory for mitigations.

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1912471
https://www.mozilla.org/security/advisories/mfsa2024-46/
https://www.mozilla.org/security/advisories/mfsa2024-47/
https://www.mozilla.org/security/advisories/mfsa2024-49/
https://www.mozilla.org/security/advisories/mfsa2024-50/

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