# CVE-2026-98005: erofs: delimit inode_share cache key components

> An ambiguity in EROFS inode cache key encoding could allow incorrect cache lookups, potentially leading to data integrity issues or information disclosure.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 25 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** DEBIAN-CVE-2026-98005, GHSA-cmc8-g72c-8f33, UBUNTU-CVE-2026-98005

## What is CVE-2026-98005?

CVE-2026-98005 is a vulnerability in Linux, published on 25 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

erofs: delimit inode_share cache key components

Previously, inode_share keys were encoded as follows:

  fingerprint || domain_id

It would be better to have a separator between the fingerprint and domain
ID so that the fingerprint won't be parsed as part of a domain ID.

Change the key encoding as follows:

  domain_id || '\0' || fingerprint

Since domain_id is a NUL-terminated string, this makes the in-memory key
indices unambiguous.

## Which versions are affected by CVE-2026-98005?


## How do I fix CVE-2026-98005?

Apply the vendor's patch.

## Is CVE-2026-98005 being exploited?

There is no known exploitation of CVE-2026-98005 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98005 and fix it if it is affected.

What it is: CVE-2026-98005 is a vulnerability in Linux, published on 25 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-98005 in the wild and no public exploit code.

Affected product: Linux. 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-2026-98005/ (Markdown: https://insights.sbomify.com/CVE-2026-98005/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98005
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98005
- OSV: https://osv.dev/vulnerability/CVE-2026-98005

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98005/
Summaries are generated and may contain mistakes; the official description above is the record.