# CVE-2026-104054: calcom cal.diy PBAC Permission BookingAccessService.ts doesUserIdHaveAccessToBooking authorization

> Attackers can bypass authorization checks in the PBAC engine to access or modify booking data without proper permissions.

- **Severity:** Medium 5.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P`)
- **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:** 2 Oct 2026
- **Updated:** 2 Oct 2026
- **Also known as:** GHSA-48q5-8whv-r6xj

## What is CVE-2026-104054?

CVE-2026-104054 is a medium-severity missing authorization vulnerability in calcom cal.diy, published on 2 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A security flaw has been discovered in calcom cal.diy up to 6.2.0. This affects the function doesUserIdHaveAccessToBooking of the file BookingAccessService.ts of the component PBAC Permission Engine. Performing a manipulation results in missing authorization. The attack can be initiated remotely. The exploit has been released to the public and may be used for attacks. The pull request to fix this issue awaits acceptance.

Weakness: CWE-863 (Incorrect Authorization), CWE-862 (Missing Authorization)

## Which versions are affected by CVE-2026-104054?


## How do I fix CVE-2026-104054?

No fix has been published for CVE-2026-104054 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-104054 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-104054 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-104054 and fix it if it is affected.

What it is: CVE-2026-104054 is a medium-severity missing authorization vulnerability in calcom cal.diy, published on 2 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-2026-104054 exists.

Affected product: calcom cal.diy. 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-2026-104054/ (Markdown: https://insights.sbomify.com/CVE-2026-104054/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-104054
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-104054
- OSV: https://osv.dev/vulnerability/CVE-2026-104054

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-104054/
Summaries are generated and may contain mistakes; the official description above is the record.