CVE-2026-2799: Use-after-free in the DOM: Core & HTML component
Use-after-free in the DOM: Core & HTML component. This vulnerability affects Firefox < 148.
Other sources
Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 148 and Thunderbird 148.
— MITRE
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 148 - Upgrade
Upgrade
Firefoxto a version that resolves this vulnerability.Fixed in 148 - Upgrade
Upgrade
Thunderbirdto a version that resolves this vulnerability.Fixed in 148
Event History
Peer vulnerabilities
Found alongside the following vulnerabilities.
- CVE-2026-2757
- CVE-2026-2794
- CVE-2026-2758
- CVE-2026-2759
- CVE-2026-2795
- CVE-2026-2760
- CVE-2026-2761
- CVE-2026-2762
- CVE-2026-2763
- CVE-2026-2764
- CVE-2026-2796
- CVE-2026-2797
- CVE-2026-2765
- CVE-2026-2766
- CVE-2026-2767
- CVE-2026-2768
- CVE-2026-2798
- CVE-2026-2769
- CVE-2026-2799
- CVE-2026-2770
- CVE-2026-2771
- CVE-2026-2772
- CVE-2026-2773
- CVE-2026-2774
- CVE-2026-2775
- CVE-2026-2776
- CVE-2026-2777
- CVE-2026-2778
- CVE-2026-2779
- CVE-2026-2800
- CVE-2026-2780
- CVE-2026-2781
- CVE-2026-2801
- CVE-2026-2782
- CVE-2026-2783
- CVE-2026-2802
- CVE-2026-2803
- CVE-2026-2784
- CVE-2026-2785
- CVE-2026-2804
- CVE-2026-2786
- CVE-2026-2805
- CVE-2026-2787
- CVE-2026-2788
- CVE-2026-2789
- CVE-2026-2806
- CVE-2026-2790
- CVE-2026-2791
- CVE-2026-2807
- CVE-2026-2792
- CVE-2026-2793
Frequently Asked Questions
What is the severity of CVE-2026-2799?
CVE-2026-2799 has a critical severity rating of 9.8 by CVSS 3.1.
How do I fix CVE-2026-2799?
To fix CVE-2026-2799, update Mozilla Firefox or Mozilla Thunderbird to version 148 or later.
What impact does CVE-2026-2799 have on users?
CVE-2026-2799 can lead to potential system compromise due to a use-after-free vulnerability in the DOM.
Which software is affected by CVE-2026-2799?
CVE-2026-2799 affects Mozilla Firefox and Mozilla Thunderbird.
When was CVE-2026-2799 published and last modified?
CVE-2026-2799 was published on February 24, 2026, and last modified on April 13, 2026.