# CVE-2022-39242: Incorrect Calculation in Frontier leads to inflated Ethereum chain gas prices

> Attackers can inflate Ethereum chain gas prices via block spamming using large refunds, causing denial of service in Frontier.

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 24 Sep 2022
- **Updated:** 23 Apr 2025
- **Also known as:** GHSA-v57h-6hmh-g2p4

## What is CVE-2022-39242?

CVE-2022-39242 is a medium-severity denial of service vulnerability in paritytech frontier, published on 24 Sep 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Frontier is an Ethereum compatibility layer for Substrate. Prior to commit d3beddc6911a559a3ecc9b3f08e153dbe37a8658, the worst case weight was always accounted as the block weight for all cases. In case of large EVM gas refunds, this can lead to block spamming attacks -- the adversary can construct blocks with transactions that have large amount of refunds or unused gases with reverts, and as a result inflate up the chain gas prices. The impact of this issue is limited in that the spamming attack would still be costly for any adversary, and it has no ability to alter any chain state. This issue has been patched in commit d3beddc6911a559a3ecc9b3f08e153dbe37a8658. There are no known workarounds.

Weakness: CWE-682 (Incorrect Calculation)

## Which versions are affected by CVE-2022-39242?

2 open source packages ship an affected version, including pallet-ethereum. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `pallet-ethereum` | crates.io | All versions to 3.0.0 | None |
| `pallet-ethereum` | crates.io | All versions to 3.0.0 | None |

Products: Parity Frontier.

## How do I fix CVE-2022-39242?

No fix has been published for CVE-2022-39242 yet. Limit exposure of the affected software until one is available.

## Is CVE-2022-39242 being exploited?

There is no known exploitation of CVE-2022-39242 in the wild and no public exploit code.

## Other vulnerabilities in paritytech frontier

- [CVE-2023-45130](https://insights.sbomify.com/CVE-2023-45130/): Frontier opcode SUICIDE touches too many storage values on large contracts (high 7.5)
- [CVE-2023-28431](https://insights.sbomify.com/CVE-2023-28431/): Frontier's modexp precompile is slow for even modulus (high 7.5)
- [CVE-2022-36008](https://insights.sbomify.com/CVE-2022-36008/): Message length overflow in frontier (high 7.1)
- [CVE-2022-21685](https://insights.sbomify.com/CVE-2022-21685/): Integer underflow in Frontier (medium 6.5)
- [CVE-2022-31111](https://insights.sbomify.com/CVE-2022-31111/): Discrepency in transfer value and actual value due to incorrect truncation in Frontier (medium 5.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-39242 and fix it if it is affected.

What it is: CVE-2022-39242 is a medium-severity denial of service vulnerability in paritytech frontier, published on 24 Sep 2022. 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-2022-39242 in the wild and no public exploit code.

Affected packages and fixed versions:
- pallet-ethereum (crates.io): affected all versions up to 3.0.0; no fix listed
- pallet-ethereum (crates.io): affected all versions up to 3.0.0; no fix listed

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-2022-39242/ (Markdown: https://insights.sbomify.com/CVE-2022-39242/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-39242
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-39242
- OSV: https://osv.dev/vulnerability/CVE-2022-39242

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-39242/
Summaries are generated and may contain mistakes; the official description above is the record.