# GHSA-qcxq-75wr-5cm8: ldap3_proto has LDAP Filter stack exhaustion

> An attacker can cause a denial of service by sending deeply nested LDAP queries that exhaust the parser stack.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 6 May 2026

## What is GHSA-qcxq-75wr-5cm8?

GHSA-qcxq-75wr-5cm8 is a denial of service vulnerability in ldap3_proto, published on 6 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

### Impact
LDAP queries are not validated for depth, which can cause the parser (both PEG and ASN) to exhaust the stack. This *may* cause a denial of service in applications that process queries.

### Workarounds
N/A

### References
Related to GHSA-r5fr-9gmv-jggh

## Which versions are affected by GHSA-qcxq-75wr-5cm8?

2 open source packages ship an affected version, including ldap3_proto.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `ldap3_proto` | crates.io | All versions | 0.7.1 |
| `ldap3_proto` | crates.io | All versions | 0.7.1 |

## How do I fix GHSA-qcxq-75wr-5cm8?

Upgrade ldap3_proto to 0.7.1 or later.

## Is GHSA-qcxq-75wr-5cm8 being exploited?

There is no known exploitation of GHSA-qcxq-75wr-5cm8 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for GHSA-qcxq-75wr-5cm8 and fix it if it is affected.

What it is: GHSA-qcxq-75wr-5cm8 is a denial of service vulnerability in ldap3_proto, published on 6 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 GHSA-qcxq-75wr-5cm8 in the wild and no public exploit code.

Affected packages and fixed versions:
- ldap3_proto (crates.io): affected all versions; fixed in 0.7.1
- ldap3_proto (crates.io): affected all versions; fixed in 0.7.1

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/GHSA-qcxq-75wr-5cm8/ (Markdown: https://insights.sbomify.com/GHSA-qcxq-75wr-5cm8/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/GHSA-qcxq-75wr-5cm8

---
From sbomify Insights: https://insights.sbomify.com/GHSA-qcxq-75wr-5cm8/
Summaries are generated and may contain mistakes; the official description above is the record.