# CVE-2026-46373: SQLFluff: Recursive Stack Overflow in Parser

> An attacker can cause a denial of service in applications using SQLFluff by submitting SQL queries with excessive nesting, triggering a stack overflow.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 9 Jun 2026
- **Updated:** 10 Jun 2026
- **Also known as:** DEBIAN-CVE-2026-46373, GHSA-wmhf-fqc8-vxhh, PYSEC-2026-209, UBUNTU-CVE-2026-46373

## What is CVE-2026-46373?

CVE-2026-46373 is a high-severity denial of service vulnerability in sqlfluff, published on 9 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

SQLFluff is a modular SQL linter and auto-formatter with support for multiple dialects and templated code. Prior to version 4.1.0, in deployments where untrusted users can provide SQL queries to be linted, an untrusted user can submit a malicious query with deliberate excessive nesting to any application using the parser to trigger a Denial of Service through resource exhaustion. This issue has been patched in version 4.1.0.

Weakness: CWE-674 (Uncontrolled Recursion)

## Which versions are affected by CVE-2026-46373?

3 open source packages ship an affected version, including sqlfluff. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `sqlfluff` | PyPI | All versions | 4.1.0 |
| `sqlfluff` | PyPI | All versions | 4.1.0 |
| `sqlfluff` | PyPI | All versions | 4.1.0 |

Products: Sqlfluff Sqlfluff.

## How do I fix CVE-2026-46373?

Upgrade sqlfluff to 4.1.0 or later.

## Is CVE-2026-46373 being exploited?

There is no known exploitation of CVE-2026-46373 in the wild and no public exploit code.

## Other vulnerabilities in sqlfluff

- [CVE-2026-46374](https://insights.sbomify.com/CVE-2026-46374/): SQLFluff: Uncontrolled Resource Consumption in Parser (high 7.5)
- [CVE-2023-36830](https://insights.sbomify.com/CVE-2023-36830/): SQLFluff vulnerability for users with access to config file, using `library_path` to call arbitrary python code. (medium 6.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-46373 and fix it if it is affected.

What it is: CVE-2026-46373 is a high-severity denial of service vulnerability in sqlfluff, published on 9 Jun 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-2026-46373 in the wild and no public exploit code.

Affected packages and fixed versions:
- sqlfluff (PyPI): affected all versions; fixed in 4.1.0
- sqlfluff (PyPI): affected all versions; fixed in 4.1.0
- sqlfluff (PyPI): affected all versions; fixed in 4.1.0

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-2026-46373/ (Markdown: https://insights.sbomify.com/CVE-2026-46373/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-46373
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-46373
- OSV: https://osv.dev/vulnerability/CVE-2026-46373

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-46373/
Summaries are generated and may contain mistakes; the official description above is the record.