Red Hat Security Advisory: thunderbird security update
A security update for Mozilla Thunderbird addresses multiple vulnerabilities including unsolicited file download, disk space exhaustion, and credential leakage via mailbox:/// links (CVE-2025-5986). This advisory from Red Hat covers Thunderbird on Red Hat Enterprise Linux 8.4. The update fixes several related CVEs and is rated as having an important security impact. No CVSS score is provided in the advisory. The update is available and should be applied to affected systems.
AI Analysis
Technical Summary
Mozilla Thunderbird, a standalone mail and newsgroup client, has multiple security vulnerabilities including unsolicited file download, disk space exhaustion, and credential leakage via mailbox:/// links as identified in CVE-2025-5986. Red Hat Product Security issued an advisory (RHSA-2025:10165) for Red Hat Enterprise Linux 8.4, providing updated Thunderbird packages that address these issues. The advisory also references additional CVEs (CVE-2025-6424, CVE-2025-6425, CVE-2025-6429, CVE-2025-6430) fixed in the update. The vendor rates the update as important and provides packages for remediation.
Potential Impact
The vulnerabilities could allow an attacker to cause unsolicited file downloads, exhaust disk space, or leak credentials via specially crafted mailbox:/// links in Thunderbird. These issues could impact confidentiality and availability of the affected system. The advisory does not report known exploits in the wild.
Mitigation Recommendations
A security update for Thunderbird is available from Red Hat for Red Hat Enterprise Linux 8.4. Users should apply the update as described in the Red Hat advisory RHSA-2025:10165 and the referenced article https://access.redhat.com/articles/11258 to remediate the vulnerabilities. No additional mitigation steps are indicated by the vendor.
Red Hat Security Advisory: thunderbird security update
Description
A security update for Mozilla Thunderbird addresses multiple vulnerabilities including unsolicited file download, disk space exhaustion, and credential leakage via mailbox:/// links (CVE-2025-5986). This advisory from Red Hat covers Thunderbird on Red Hat Enterprise Linux 8.4. The update fixes several related CVEs and is rated as having an important security impact. No CVSS score is provided in the advisory. The update is available and should be applied to affected systems.
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Mozilla Thunderbird, a standalone mail and newsgroup client, has multiple security vulnerabilities including unsolicited file download, disk space exhaustion, and credential leakage via mailbox:/// links as identified in CVE-2025-5986. Red Hat Product Security issued an advisory (RHSA-2025:10165) for Red Hat Enterprise Linux 8.4, providing updated Thunderbird packages that address these issues. The advisory also references additional CVEs (CVE-2025-6424, CVE-2025-6425, CVE-2025-6429, CVE-2025-6430) fixed in the update. The vendor rates the update as important and provides packages for remediation.
Potential Impact
The vulnerabilities could allow an attacker to cause unsolicited file downloads, exhaust disk space, or leak credentials via specially crafted mailbox:/// links in Thunderbird. These issues could impact confidentiality and availability of the affected system. The advisory does not report known exploits in the wild.
Mitigation Recommendations
A security update for Thunderbird is available from Red Hat for Red Hat Enterprise Linux 8.4. Users should apply the update as described in the Red Hat advisory RHSA-2025:10165 and the referenced article https://access.redhat.com/articles/11258 to remediate the vulnerabilities. No additional mitigation steps are indicated by the vendor.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2025:10165
- Cve Count
- 5
- Additional Cves
- ["CVE-2025-6424","CVE-2025-6425","CVE-2025-6429","CVE-2025-6430"]
Threat ID: 6a419cb927e9c79719abe72d
Added to database: 06/28/2026, 22:14:17 UTC
Last enriched: 06/28/2026, 22:35:03 UTC
Last updated: 09/10/2026, 19:36:51 UTC
Views: 42
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