# GHSA-5x78-73v4-xg6w: Unbounded SCRAM iteration count allows a malicious server to cause CPU-exhaustion denial of service

> A malicious server can cause client CPU exhaustion via unbounded SCRAM iteration counts, impacting applications connecting to untrusted databases.

- **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:** 12 Jun 2026
- **Also known as:** RUSTSEC-2026-0179

## What is GHSA-5x78-73v4-xg6w?

GHSA-5x78-73v4-xg6w is a denial of service vulnerability in postgres-protocol, published on 12 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A malicious, compromised, or man-in-the-middle server can supply an arbitrarily
large SCRAM-SHA-256 PBKDF2 iteration count during authentication. The client
runs it inline with no upper bound, pinning a `tokio` worker thread for minutes
per connection, possibly stalling the whole async runtime.

Applications that connect only to a trusted database are not exposed; the risk
applies to clients that may connect to untrusted or user-supplied servers, or
whose connection can be intercepted by a man-in-the-middle.

## Which versions are affected by GHSA-5x78-73v4-xg6w?

3 open source packages ship an affected version, including postgres-protocol.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `postgres-protocol` | crates.io | From 0.3.0 | 0.6.12 |
| `postgres-protocol` | crates.io | From 0.3.0 | 0.6.12 |
| `postgres-protocol` | crates.io | From 0.3.0 | 0.6.12 |

## How do I fix GHSA-5x78-73v4-xg6w?

Upgrade postgres-protocol to 0.6.12 or later.

## Is GHSA-5x78-73v4-xg6w being exploited?

There is no known exploitation of GHSA-5x78-73v4-xg6w in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for GHSA-5x78-73v4-xg6w and fix it if it is affected.

What it is: GHSA-5x78-73v4-xg6w is a denial of service vulnerability in postgres-protocol, published on 12 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 GHSA-5x78-73v4-xg6w in the wild and no public exploit code.

Affected packages and fixed versions:
- postgres-protocol (crates.io): affected from 0.3.0; fixed in 0.6.12
- postgres-protocol (crates.io): affected from 0.3.0; fixed in 0.6.12
- postgres-protocol (crates.io): affected from 0.3.0; fixed in 0.6.12

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-5x78-73v4-xg6w/ (Markdown: https://insights.sbomify.com/GHSA-5x78-73v4-xg6w/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/GHSA-5x78-73v4-xg6w

---
From sbomify Insights: https://insights.sbomify.com/GHSA-5x78-73v4-xg6w/
Summaries are generated and may contain mistakes; the official description above is the record.