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CVE-2026-2778
Sandbox escape due to incorrect boundary conditions in the DOM: Core & HTML component
Critical10.0EPSS 0.56%
- Published
- Updated
- Reserved
- Assigned by
- mozilla
Description
Sandbox escape due to incorrect boundary conditions in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 148, Firefox ESR 115.33, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.
Timeline
ID reserved
By mozilla
- 5 days later
· 5 days later
Published
- 5 months later
· 5 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| CISA-ADPADP (enrichment) | 3.1 | Critical10.0 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H |
| redhat-SADPADP (enrichment) | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H |
| NVDNVD · Modified | 3.1 | Critical10.0 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.56% · top 53% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: total
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 10.0.
Weakness
Affected products
- unaffected 115.33 – ≤ 115.*
- unaffected 140.8 – ≤ 140.*
- unaffected 148 – ≤ *
- unaffected 140.8 – ≤ 140.*
- unaffected 148 – ≤ *
References (34)
- https://bugzilla.mozilla.org/show_bug.cgi?id=2016358 (opens in a new tab)
- https://www.mozilla.org/security/advisories/mfsa2026-13/ (opens in a new tab)
- https://www.mozilla.org/security/advisories/mfsa2026-14/ (opens in a new tab)
- https://www.mozilla.org/security/advisories/mfsa2026-15/ (opens in a new tab)
- https://www.mozilla.org/security/advisories/mfsa2026-16/ (opens in a new tab)
- https://www.mozilla.org/security/advisories/mfsa2026-17/ (opens in a new tab)
- https://access.redhat.com/security/cve/CVE-2026-2778 (opens in a new tab)vdb-entryx_refsource_REDHAT
- RHBZ#2442335 (opens in a new tab)issue-trackingx_refsource_REDHAT
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-2778.json (opens in a new tab)x_sadp-csaf-vex
- https://access.redhat.com/errata/RHSA-2026:3984 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:3976 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:4260 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:3361 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:3517 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:3338 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:3515 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:3492 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:4432 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:3491 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:3980 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:3495 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:3979 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:3494 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:4022 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:3493 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:3983 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:4152 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:3978 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:3496 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:3981 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:3497 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:3982 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:3339 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2026:3516 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-2778)Record last updated .