High [CVE-2026-74987] Internally found bugs fixed in Firefox ESR 140.14, Firefox ESR 153.1 and Firefox 154
This high-severity Red Hat Linux advisory covers CVE-2026-74987 affecting Red Hat Enterprise Linux 10.0 Extended Update Support, Red Hat Enterprise Linux 7 Extended Lifecycle Support, Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support.
Aggregated and source-linked by VulniPulse. Data sources, validation and limitations.
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Summary
Internally found bugs present in Thunderbird ESR 140.13, Thunderbird ESR 153.0 and Thunderbird 153. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited.
A flaw was found in Firefox and Thunderbird. Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.
Red Hat severity: Important — CVSS 7.5 (CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H). Weakness: CWE-787.
Affected products named by the advisory: Red Hat Enterprise Linux 10.0 Extended Update Support; Red Hat Enterprise Linux 7 Extended Lifecycle Support; Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support; Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On; and 10 more.
Affected versions
No affected-version range was extracted from the source record. The vendor advisory is authoritative — check it before change work.
Official advisory · high-confidence parse· fetched 9 days ago·verify at source
- 140.14
- 153.1
- firefox-0:140.14.0-1.el10_2
- thunderbird-0:140.14.0-1.el10_2
- firefox-0:140.14.0-1.el10_0
- thunderbird-0:140.14.0-1.el10_0
- firefox-0:140.14.0-1.el7_9
- firefox-0:140.14.0-1.el8_10
- thunderbird-0:140.14.0-1.el8_10
- firefox-0:140.14.0-1.el8_4
- thunderbird-0:140.14.0-1.el8_4
- firefox-0:140.14.0-1.el8_6
- thunderbird-0:140.14.0-1.el8_6
- firefox-0:140.14.0-1.el8_8
- thunderbird-0:140.14.0-1.el8_8
- firefox-0:140.14.0-1.el9_8
- thunderbird-0:140.14.0-1.el9_8
- thunderbird-0:140.14.0-1.el9_2
- firefox-0:140.14.0-1.el9_2
- firefox-0:140.14.0-1.el9_4
- thunderbird-0:140.14.0-1.el9_4
- firefox-0:140.14.0-1.el9_6
- thunderbird-0:140.14.0-1.el9_6
- RHSA-2026:58899
- RHSA-2026:65159
- RHSA-2026:64813
- RHSA-2026:65633
- RHSA-2026:65442
- RHSA-2026:58898
- RHSA-2026:65160
- RHSA-2026:65111
- RHSA-2026:65764
- RHSA-2026:65110
- RHSA-2026:65757
- RHSA-2026:64814
- RHSA-2026:65765
- RHSA-2026:58897
- RHSA-2026:65158
- RHSA-2026:65766
- RHSA-2026:65888
- RHSA-2026:65105
- RHSA-2026:65669
- RHSA-2026:65103
Official advisory · high-confidence parse· fetched 9 days ago·verify at source
Mitigation
Upgrade to a fixed release: 140.14, 153.1, firefox-0:140.14.0-1.el10_2, thunderbird-0:140.14.0-1.el10_2, firefox-0:140.14.0-1.el10_0, thunderbird-0:140.14.0-1.el10_0. That is the remediation for this advisory.
The vendor advisory may list additional interim mitigations or workarounds not captured here — review it before change work.
Official advisory · high-confidence parse· fetched 9 days ago·verify at source
Discussion(0)
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