Detections
Analytics
CVE-2026-0891
high
Description
Memory safety bugs present in Firefox ESR 140.6, Thunderbird ESR 140.6, Firefox 146 and Thunderbird 146. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 147, Firefox ESR 140.7, Thunderbird 147, and Thunderbird 140.7.
References
https://www.mozilla.org/security/advisories/mfsa2026-05/
https://www.mozilla.org/security/advisories/mfsa2026-04/
https://www.mozilla.org/security/advisories/mfsa2026-03/
https://www.mozilla.org/security/advisories/mfsa2026-01/
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-0891.json
https://bugzilla.redhat.com/show_bug.cgi?id=2428963
https://bugzilla.mozilla.org/buglist.cgi?bug_id=1964722%2C2000981%2C2003100%2C2003278
https://access.redhat.com/security/cve/CVE-2026-0891
https://access.redhat.com/errata/RHSA-2026:2286
https://access.redhat.com/errata/RHSA-2026:2271
https://access.redhat.com/errata/RHSA-2026:2231
https://access.redhat.com/errata/RHSA-2026:2220
https://access.redhat.com/errata/RHSA-2026:2074
https://access.redhat.com/errata/RHSA-2026:2073
https://access.redhat.com/errata/RHSA-2026:2070
https://access.redhat.com/errata/RHSA-2026:2069
https://access.redhat.com/errata/RHSA-2026:2047
https://access.redhat.com/errata/RHSA-2026:2044
https://access.redhat.com/errata/RHSA-2026:2043
https://access.redhat.com/errata/RHSA-2026:2041
https://access.redhat.com/errata/RHSA-2026:1487
https://access.redhat.com/errata/RHSA-2026:1471
https://access.redhat.com/errata/RHSA-2026:1462
https://access.redhat.com/errata/RHSA-2026:1461
https://access.redhat.com/errata/RHSA-2026:1415
https://access.redhat.com/errata/RHSA-2026:1414
https://access.redhat.com/errata/RHSA-2026:1413
https://access.redhat.com/errata/RHSA-2026:1320
https://access.redhat.com/errata/RHSA-2026:0924