CVE-2022-40960

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2022-12-22 · updated 2026-06-17
Weakness: CWE-416

Description

Concurrent use of the URL parser with non-UTF-8 data was not thread-safe. This could lead to a use-after-free causing a potentially exploitable crash. This vulnerability affects Firefox ESR < 102.3, Thunderbird < 102.3, and Firefox < 105.

Affected products

Mozilla Firefox: before 105.0 — fixed in 105.0
Mozilla Firefox ESR: before 102.3 — fixed in 102.3
Mozilla Thunderbird: before 102.3 — fixed in 102.3

How to fix

Upgrade to a fixed version: Mozilla Firefox 105.0; Mozilla Firefox ESR 102.3; Mozilla Thunderbird 102.3. Check the vendor advisory for mitigations.

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1787633
https://www.mozilla.org/security/advisories/mfsa2022-40/
https://www.mozilla.org/security/advisories/mfsa2022-41/
https://www.mozilla.org/security/advisories/mfsa2022-42/
https://bugzilla.mozilla.org/show_bug.cgi?id=1787633
https://www.mozilla.org/security/advisories/mfsa2022-40/
https://www.mozilla.org/security/advisories/mfsa2022-41/
https://www.mozilla.org/security/advisories/mfsa2022-42/

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