# RHSA-2025:8203: thunderbird security update

RHSA-2025:8203, released May 27, 2025, fixes 4 CVEs in thunderbird (version 0:128.10.1-1.el9_6). None of them is reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/fix/linux/rhsa-2025-8203
- Platform: Linux
- Released: May 27, 2025
- Priority: High (Closes CVE-2025-3909, high severity)
- CVEs: 4, exploited: 0, on CISA KEV: 0
- Vendor advisory: https://access.redhat.com/errata/RHSA-2025:8203

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [thunderbird](https://patchblox.com/security/data/product/linux/thunderbird.md) | RHEL 9 | 0:128.10.1-1.el9_6 |

## CVEs this fix closes

| CVE | Priority | Title | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2025-3909](https://patchblox.com/security/data/cve/CVE-2025-3909.md) | High | JavaScript Execution via Spoofed PDF Attachment and file:/// Link | 8.8 | 0.0047 |  |
| [CVE-2025-3875](https://patchblox.com/security/data/cve/CVE-2025-3875.md) | High | Sender Spoofing via Malformed From Header in Thunderbird | 8.8 | 0.0040 |  |
| [CVE-2025-3932](https://patchblox.com/security/data/cve/CVE-2025-3932.md) | High | Tracking Links in Attachments Bypassed Remote Content Blocking | 8.8 | 0.0039 |  |
| [CVE-2025-3877](https://patchblox.com/security/data/cve/CVE-2025-3877.md) | High | thunderbird: Rejected reason: This CVE was marked as fixed, but due to other code landing - was not actually fixed | 8.8 | n/a |  |

---

Data as of 2026-11-07T12:40:37Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo