# CVE-2026-29200: Auth bypass in Comet Backup

> Tenant administrators can impersonate end-user accounts of other tenants via a vulnerable API call, leading to unauthorized access.

- **Severity:** Critical 9.9 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 4 May 2026
- **Updated:** 4 May 2026
- **Also known as:** GHSA-2fxc-8v96-j5f3

## What is CVE-2026-29200?

CVE-2026-29200 is a critical authentication bypass vulnerability in WebPros Comet Backup, published on 4 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A critical IDOR vulnerability has been discovered in Comet Backup affecting all versions from 20.11.0 to 26.1.1 and 26.2.1. The vulnerability allows a tenant administrator to impersonate any end-user account of other tenants on the same server via a vulnerable API call.

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

## Which versions are affected by CVE-2026-29200?


## How do I fix CVE-2026-29200?

No fix has been published for CVE-2026-29200 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-29200 being exploited?

There is no known exploitation of CVE-2026-29200 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-29200 and fix it if it is affected.

What it is: CVE-2026-29200 is a critical authentication bypass vulnerability in WebPros Comet Backup, published on 4 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-29200 in the wild and no public exploit code.

Affected product: WebPros Comet Backup. 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-2026-29200/ (Markdown: https://insights.sbomify.com/CVE-2026-29200/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-29200
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-29200
- OSV: https://osv.dev/vulnerability/CVE-2026-29200

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-29200/
Summaries are generated and may contain mistakes; the official description above is the record.