# CVE-2026-118174: thunderbird: When a message containing an OpenPGP key attachment was displayed, Thunderbird automatically loaded the attachment's...

CVE-2026-118174 is fixed in thunderbird on 1 platform, first by DEBIAN-CVE-2026-118174, released October 31, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-118174
- Priority: Routine
- CVSS: 6.5 (medium)
- EPSS: 0.0037
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Oct 27, 2026

## Description

When a message containing an OpenPGP key attachment was displayed, Thunderbird automatically loaded the attachment's content to offer importing the key. A sender could mark the attachment as an external attachment pointing to an arbitrary URL, which Thunderbird then loaded without any user interaction, bypassing remote content blocking. On Windows, a URL pointing to an attacker-controlled network share could leak the user's NTLM credentials. The NTLM credential leak only affects Thunderbird on Windows. On other operating systems, the issue allowed a remote request that bypassed remote content blocking. 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-2026-118174](https://patchblox.com/security/data/fix/linux/debian-cve-2026-118174.md) | Oct 31, 2026 |
| Linux | thunderbird Debian 13.5 (trixie) | 1:153.6.0esr-1~deb13u1 | [DEBIAN-CVE-2026-118174](https://patchblox.com/security/data/fix/linux/debian-cve-2026-118174.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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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