Information disclosure due to malicious IMAP server response
Published Sep 1, 2026
7.5
HIGHCVSS 3.1
EPSS 0.27%
Description
A malicious IMAP server can trigger use-after-free and heap-memory disclosure by sending a crafted ID response. Heap contents can ultimately be persisted to prefs.js. This vulnerability was fixed in Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2.
Affected products
No data.
- < 140.15.0
- ≥ 141.0 · < 153.2.0
- ≥ 154.0 · < 155.0
No data.
Red Hat Enterprise Linux 10
rhel10/thunderbird-flatpak
Affected
Red Hat Enterprise Linux 10
thunderbird
Affected
Red Hat Enterprise Linux 6
thunderbird
Out of support scope
Red Hat Enterprise Linux 7
thunderbird
Out of support scope
Red Hat Enterprise Linux 8
thunderbird
Affected
Red Hat Enterprise Linux 9
thunderbird
Affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 10 | rhel10/thunderbird-flatpak | Affected | n/a |
| Red Hat Enterprise Linux 10 | thunderbird | Affected | n/a |
| Red Hat Enterprise Linux 6 | thunderbird | Out of support scope | n/a |
| Red Hat Enterprise Linux 7 | thunderbird | Out of support scope | n/a |
| Red Hat Enterprise Linux 8 | thunderbird | Affected | n/a |
| Red Hat Enterprise Linux 9 | thunderbird | Affected | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.
References (10)
- https://access.redhat.com/security/cve/CVE-2026-84641 Vendor Advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=2057805 Permissions Required
- https://bugzilla.redhat.com/show_bug.cgi?id=2527115 Issue Tracking
- https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-69710 Advisory
- https://nvd.nist.gov/vuln/detail/CVE-2026-84641
- https://www.cve.org/CVERecord?id=CVE-2026-84641
- https://www.mozilla.org/security/advisories/mfsa2026-86/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-87/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-87/#CVE-2026-84641
- https://www.mozilla.org/security/advisories/mfsa2026-88/ Vendor Advisory
Change history (0)
No recorded changes yet.
CVE.org / MITRE
CISA Vulnrichment
GitHub
No data