# CVE-2026-8933: snap-confine Local Privilege Escalation via Capabilities Misconfiguration or Flaw in Execution Environment Setup

> Local attackers can escalate privileges to root in Ubuntu systems using snap-confine with set-capabilities due to a flaw in execution environment setup.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 21 Jul 2026
- **Updated:** 22 Jul 2026
- **Also known as:** DEBIAN-CVE-2026-8933, GHSA-fxqr-j4gx-622c, UBUNTU-CVE-2026-8933

## What is CVE-2026-8933?

CVE-2026-8933 is a high-severity vulnerability in Canonical Ubuntu 22.04 LTS, published on 21 Jul 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A local privilege escalation vulnerability exists in snap-confine, a set-capabilities core component used internally by Canonical snapd to construct the secure execution environment for snap applications. This vulnerability uniquely affects versions of snap-confine configured with set-capabilities (rather than standard set-uid-root installations).
Due to a flaw in how privilege boundaries or security sandboxes are initialized when the binary runs under limited ambient capabilities, a local, unprivileged attacker can exploit this behavior to bypass intended restrictions and execute arbitrary code. Successful exploitation allows the local user to elevate their privileges to full root authority.

Weakness: CWE-250 (Execution with Unnecessary Privileges)

## Which versions are affected by CVE-2026-8933?


## How do I fix CVE-2026-8933?

Apply the vendor's patch.

## Is CVE-2026-8933 being exploited?

There is no known exploitation of CVE-2026-8933 in the wild and no public exploit code.

Public exploit code:

- https://github.com/songzzzz/CVE-2026-8933 (github_poc): https://github.com/songzzzz/CVE-2026-8933
- https://github.com/yifengchen-cc/CVE-2026-8933 (github_poc): https://github.com/yifengchen-cc/CVE-2026-8933

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-8933 and fix it if it is affected.

What it is: CVE-2026-8933 is a high-severity vulnerability in Canonical Ubuntu 22.04 LTS, published on 21 Jul 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-2026-8933 in the wild and no public exploit code.

Affected product: Canonical Ubuntu 22.04 LTS. 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-2026-8933/ (Markdown: https://insights.sbomify.com/CVE-2026-8933/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-8933
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-8933
- OSV: https://osv.dev/vulnerability/CVE-2026-8933

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-8933/
Summaries are generated and may contain mistakes; the official description above is the record.