# CVE-2026-118175: thunderbird: When replying to, forwarding, or editing a crafted email message as new, Thunderbird could embed parts of a different...

CVE-2026-118175 is fixed in thunderbird on 1 platform, first by DEBIAN-CVE-2026-118175, released October 31, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-118175
- Priority: High
- CVSS: 7.5 (high)
- EPSS: 0.0040
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Oct 27, 2026

## Description

When replying to, forwarding, or editing a crafted email message as new, Thunderbird could embed parts of a different message stored in the same folder into the message being composed, without showing a blocked content warning. If the user sent the message, the content of the other message was disclosed to the recipients. This vulnerability was fixed in Thunderbird 159 and Thunderbird 153.6.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | thunderbird Debian 12.15 (bookworm) | 1:153.6.0esr-1~deb12u2 | [DEBIAN-CVE-2026-118175](https://patchblox.com/security/data/fix/linux/debian-cve-2026-118175.md) | Oct 31, 2026 |
| Linux | thunderbird Debian 13.5 (trixie) | 1:153.6.0esr-1~deb13u1 | [DEBIAN-CVE-2026-118175](https://patchblox.com/security/data/fix/linux/debian-cve-2026-118175.md) | Oct 31, 2026 |

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Data as of 2026-11-09T13:31:49Z 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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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