# CVE-2026-7724: PrefectHQ prefect Webhook/Notification validate_restricted_url toctou

> Attackers can bypass URL restrictions in Prefect webhooks via a race condition, requiring high complexity and remote access.

- **Severity:** Low 2.3 (`CVSS:4.0/AV:N/AC:H/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:** Yes
- **Published:** 4 May 2026
- **Updated:** 5 May 2026
- **Also known as:** GHSA-p3pq-hxmr-vqqr, PYSEC-2026-2959

## What is CVE-2026-7724?

CVE-2026-7724 is a low-severity vulnerability in PrefectHQ prefect, published on 4 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A vulnerability has been found in PrefectHQ prefect up to 3.6.28.dev1. Affected by this vulnerability is the function validate_restricted_url of the component Webhook/Notification. The manipulation leads to time-of-check time-of-use. It is possible to initiate the attack remotely. The attack is considered to have high complexity. The exploitation appears to be difficult. The exploit has been disclosed to the public and may be used. Upgrading to version 3.6.28.dev2 addresses this issue. The identifier of the patch is 7c70ac54a5e101431d83b9f2681ec88d5e0021ed. Upgrading the affected component is advised. The vendor was contacted early, responded in a very professional manner and quickly released a fixed version of the affected product.

Weakness: CWE-367 (Time-of-check Time-of-use (TOCTOU) Race Condition), CWE-362 (Concurrent Execution using Shared Resource with Improper Synchronization)

## Which versions are affected by CVE-2026-7724?

3 open source packages ship an affected version, including prefect.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `prefect` | PyPI | All versions | 3.6.28.dev2 |
| `prefect` | PyPI | All versions | 3.6.28.dev2 |
| `prefect` | PyPI | All versions | 3.6.28.dev2 |

## How do I fix CVE-2026-7724?

Upgrade prefect to 3.6.28.dev2 or later.

## Is CVE-2026-7724 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-7724 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-7724 and fix it if it is affected.

What it is: CVE-2026-7724 is a low-severity vulnerability in PrefectHQ prefect, published on 4 May 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-2026-7724 exists.

Affected packages and fixed versions:
- prefect (PyPI): affected all versions; fixed in 3.6.28.dev2
- prefect (PyPI): affected all versions; fixed in 3.6.28.dev2
- prefect (PyPI): affected all versions; fixed in 3.6.28.dev2

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-2026-7724/ (Markdown: https://insights.sbomify.com/CVE-2026-7724/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-7724
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-7724
- OSV: https://osv.dev/vulnerability/CVE-2026-7724

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-7724/
Summaries are generated and may contain mistakes; the official description above is the record.