# CVE-2026-48113: Chisel: ACL Bypass via Post-Handshake SSH Channel ExtraData Injection

> Authenticated clients can bypass ACL restrictions to tunnel traffic to arbitrary destinations due to missing authorization checks on subsequent SSH channels.

- **Severity:** High 8.5 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:H/SI:H/SA:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 3 Aug 2026
- **Updated:** 4 Aug 2026
- **Also known as:** GHSA-24fp-5v3p-rvpw, GO-2026-5054

## What is CVE-2026-48113?

CVE-2026-48113 is a high-severity missing authorization vulnerability in jpillora chisel, published on 3 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Chisel is a TCP/UDP tunnel, transported over HTTP and secured via SSH. In versions prior to 1.11.5, authenticated clients can bypass --authfile ACL restrictions and tunnel traffic to arbitrary destinations reachable from the server. The ACL is enforced only during the initial handshake against declared remotes, but never on subsequent SSH channels that carry actual traffic. A malicious client can authenticate with a permitted remote, then open channels to any host:port it wants. This issue has been fixed in version 1.11.5.

Weakness: CWE-863 (Incorrect Authorization)

## Which versions are affected by CVE-2026-48113?

3 open source packages ship an affected version, including github.com/jpillora/chisel.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/jpillora/chisel` | Go | All versions | 1.11.5 |
| `github.com/jpillora/chisel` | Go | All versions | 1.11.5 |
| `github.com/jpillora/chisel` | Go | All versions | 1.11.5 |

## How do I fix CVE-2026-48113?

Upgrade github.com/jpillora/chisel to 1.11.5 or later.

## Is CVE-2026-48113 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-48113 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-48113 and fix it if it is affected.

What it is: CVE-2026-48113 is a high-severity missing authorization vulnerability in jpillora chisel, published on 3 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-48113 exists.

Affected packages and fixed versions:
- github.com/jpillora/chisel (Go): affected all versions; fixed in 1.11.5
- github.com/jpillora/chisel (Go): affected all versions; fixed in 1.11.5
- github.com/jpillora/chisel (Go): affected all versions; fixed in 1.11.5

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-2026-48113/ (Markdown: https://insights.sbomify.com/CVE-2026-48113/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-48113
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-48113
- OSV: https://osv.dev/vulnerability/CVE-2026-48113

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-48113/
Summaries are generated and may contain mistakes; the official description above is the record.