# CVE-2026-118178: RSS feed could redirect its subscription to a local file or network share


- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Fix available:** No
- **Published:** 27 Oct 2026
- **Updated:** 27 Oct 2026
- **Also known as:** DEBIAN-CVE-2026-118178, GHSA-6j4v-p75m-p9wm, UBUNTU-CVE-2026-118178

## What is CVE-2026-118178?

CVE-2026-118178 is a vulnerability in Mozilla Thunderbird, published on 27 Oct 2026. 

### Official description

A remote RSS feed could use the itunes:new-feed-url or newLocation element to permanently change its stored subscription URL to a file: URL. Thunderbird then read that location on every feed update. This allowed a malicious feed, or an attacker able to modify a feed delivered over HTTP, to make Thunderbird read local files and, on Windows, connect to an attacker-controlled network share, which could leak the user's NTLM credentials.
The NTLM credential leak only affects Thunderbird on Windows. Other operating systems are affected by the local file read only. This vulnerability was fixed in Thunderbird 159 and Thunderbird 153.6.

## Which versions are affected by CVE-2026-118178?


## How do I fix CVE-2026-118178?

No fix has been published for CVE-2026-118178 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-118178 being exploited?

There is no known exploitation of CVE-2026-118178 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-118178 and fix it if it is affected.

What it is: CVE-2026-118178 is a vulnerability in Mozilla Thunderbird, published on 27 Oct 2026. 
Exploitation: There is no known exploitation of CVE-2026-118178 in the wild and no public exploit code.

Affected product: Mozilla Thunderbird. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-118178/ (Markdown: https://insights.sbomify.com/CVE-2026-118178/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-118178
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-118178
- OSV: https://osv.dev/vulnerability/CVE-2026-118178

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-118178/
Summaries are generated and may contain mistakes; the official description above is the record.