Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
The pallet-ethereum crate, versions up to and including 3.0.0, fails to validate input data size, so invalid transactions can be included in the Ethereum block state. The source says these transactions cannot change Ethereum or Substrate state, since the EVM engine rejects them, and Substrate extrinsic size limits further restrict the impact. No fixed version is listed, and the source gives no workaround.
Not analysed yet
We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.
Severity and exploitation
| Score | Rating | CVSS | Vector | Source |
|---|---|---|---|---|
| 5.3 | Medium | 3.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N | CNA (GitHub_M) |
- CISA KEV Not listed.
- EPSS 0.012, the 68th percentile, on 9 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Oct 2026, 15:18 UTC First seen by agentprime
- 31 Oct 2026, 15:18 UTC Confirmed by OSV
Sources
- GitHub Advisory Database: GHSA-hw4v-5x4h-c3xm
- OSV: GHSA-hw4v-5x4h-c3xm
- github.com/paritytech/frontier/security/advisories/GHSA-hw4v-5x4h-c3xm
- nvd.nist.gov/vuln/detail/CVE-2021-39193
- github.com/paritytech/frontier/pull/465
- github.com/paritytech/frontier/pull/465/commits/8a2b890a2fb477d5fedd0e4335b00623832849ae
- github.com/paritytech/frontier/commit/0b962f218f0cdd796dadfe26c3f09e68f7861b26
- github.com/paritytech/frontier/commit/dd112e
- github.com/polkadot-evm/frontier