CVE-2026-74936: Use-after-free in the JavaScript: WebAssembly component
Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, and Firefox ESR 153.1.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 140.14 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 154 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 153.1 - Upgrade
Upgrade
Firefoxto a version that resolves this vulnerability.Fixed in 154 - Upgrade
Upgrade
Firefox ESRto a version that resolves this vulnerability.Fixed in 140.14 - Upgrade
Upgrade
Firefox ESRto a version that resolves this vulnerability.Fixed in 153.1
Event History
Parent advisories
This vulnerability appears in the following advisories.
Peer vulnerabilities
Found alongside the following vulnerabilities.
- CVE-2026-74934
- CVE-2026-74935
- CVE-2026-74936
- CVE-2026-74939
- CVE-2026-74940
- CVE-2026-74941
- CVE-2026-74942
- CVE-2026-74943
- CVE-2026-74944
- CVE-2026-74945
- CVE-2026-74946
- CVE-2026-74948
- CVE-2026-74949
- CVE-2026-74953
- CVE-2026-74957
- CVE-2026-74959
- CVE-2026-74960
- CVE-2026-74962
- CVE-2026-74963
- CVE-2026-74964
- CVE-2026-74965
- CVE-2026-74967
- CVE-2026-74969
- CVE-2026-74971
- CVE-2026-74972
- CVE-2026-74973
- CVE-2026-74974
- CVE-2026-74976
- CVE-2026-74983
- CVE-2026-74987
- CVE-2026-74990
- CVE-2026-75874
- CVE-2026-74937
- CVE-2026-74938
- CVE-2026-74947
- CVE-2026-74950
- CVE-2026-74951
- CVE-2026-74952
- CVE-2026-74954
- CVE-2026-74955
- CVE-2026-74956
- CVE-2026-74958
- CVE-2026-74961
- CVE-2026-74966
- CVE-2026-74968
- CVE-2026-74970
- CVE-2026-74975
- CVE-2026-74977
- CVE-2026-74978
- CVE-2026-74979
- CVE-2026-74980
- CVE-2026-74981
- CVE-2026-74982
- CVE-2026-74984
- CVE-2026-74985
- CVE-2026-74986
- CVE-2026-74988
- CVE-2026-74989
Frequently Asked Questions
Which Firefox releases contain the fix?
Firefox versions earlier than Firefox 154, Firefox ESR 140.14, and Firefox ESR 153.1 are affected. Updating to the applicable fixed release is the remediation identified in the available data.
What is known about exploitation conditions and temporary mitigations?
The available information identifies the affected component as JavaScript: WebAssembly and classifies the issue as a use-after-free. It does not state exploit prerequisites, affected default settings, mitigations short of updating, or detection indicators.