# CVE-2026-110611: REBUILD through 4.5.0 Authorization Bypass via aibot2 Chat Endpoints chatid

> Authenticated users can access or modify other users' AI chat sessions by manipulating the chatid parameter in REBUILD application endpoints.

- **Severity:** Medium 6.0 (`CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 14 Oct 2026
- **Updated:** 20 Oct 2026
- **Also known as:** GHSA-c434-7979-wrg6

## What is CVE-2026-110611?

CVE-2026-110611 is a medium-severity missing authorization vulnerability in getrebuild rebuild, published on 14 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

REBUILD through 4.5.0 contains an authorization bypass vulnerability in AiBot2Controller /aibot2 endpoints that act on a caller-supplied chatid without verifying ownership. Authenticated low-privilege users can supply another user's chatid to chat-init, chat-delete, chat-feedback, or chat-stream-stop to read, delete, exfiltrate, or interrupt AI assistant conversations.

Weakness: CWE-639 (Authorization Bypass Through User-Controlled Key)

## Which versions are affected by CVE-2026-110611?


## How do I fix CVE-2026-110611?

No fix has been published for CVE-2026-110611 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-110611 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-110611 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-110611 and fix it if it is affected.

What it is: CVE-2026-110611 is a medium-severity missing authorization vulnerability in getrebuild rebuild, published on 14 Oct 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-2026-110611 exists.

Affected product: getrebuild rebuild. 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-2026-110611/ (Markdown: https://insights.sbomify.com/CVE-2026-110611/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-110611
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-110611
- OSV: https://osv.dev/vulnerability/CVE-2026-110611

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-110611/
Summaries are generated and may contain mistakes; the official description above is the record.