# CVE-2020-26242: GO-2021-0103 - Denial of service in github.com/holiman/uint256

Source: https://junglewise.ai/threats/cve-2020-26242-denial-of-service-in-geth  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2021-07-28  
License: CC BY 4.0 with a link back

CVE-2020-26242 · Severity: low · CVSS 3.1 · Published 2021-07-28

Denial of service in github.com/holiman/uint256

Technologies: [github.com/ethereum/go-ethereum (Go)](https://junglewise.ai/threats/technologies/github-com-ethereum-go-ethereum). Vendors: [Go](https://junglewise.ai/threats/vendors/go).

## Quick answers

**Is CVE-2020-26242 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2020-26242 being exploited in the wild.

**How severe is CVE-2020-26242?** Low severity, with a CVSS score of 3.1, published 28 July 2021.

**Which products and versions are affected?** github.com/ethereum/go-ethereum (Go) SEMVER:introduced=1.9.16,fixed=1.9.18; github.com/holiman/uint256 (Go) SEMVER:introduced=0.1.0,fixed=1.1.1.

**Is there a fix for CVE-2020-26242?** Yes. github.com/ethereum/go-ethereum (Go): upgrade to 1.9.18 or later; github.com/holiman/uint256 (Go): upgrade to 1.1.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2020-26242?** Check whether you run github.com/ethereum/go-ethereum (Go) or github.com/holiman/uint256 (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- github.com/ethereum/go-ethereum (Go): upgrade to 1.9.18 or later

  ```sh
  go get github.com/ethereum/go-ethereum@v1.9.18
  ```

- github.com/holiman/uint256 (Go): upgrade to 1.1.1 or later

  ```sh
  go get github.com/holiman/uint256@v1.1.1
  ```


## Affected products

- github.com/ethereum/go-ethereum (Go) SEMVER:introduced=1.9.16,fixed=1.9.18
- github.com/holiman/uint256 (Go) SEMVER:introduced=0.1.0,fixed=1.1.1

## Identifiers

- CVE-2020-26242
- GHSA-jm5c-rv3w-w83m
- GO-2021-0103

## Related threats

- [GO-2026-4511 - Go Ethereum Improperly Validates the ECIES Public Key in RLPx Handshake in github.com/ethereum/go-ethereum](https://junglewise.ai/threats/cve-2026-26315-go-ethereum-improperly-validates-the-ecies-public-key-in-rlpx)
- [GO-2026-4507 - Go Ethereum affected by crash via malicious p2p message in github.com/ethereum/go-ethereum](https://junglewise.ai/threats/cve-2026-26314-go-ethereum-affected-by-dos-via-malicious-p2p-message)
- [GO-2026-4508 - Go Ethereum affected by DoS via malicious p2p message in github.com/ethereum/go-ethereum](https://junglewise.ai/threats/cve-2026-26313-go-ethereum-affected-by-dos-via-malicious-p2p-message)
- [GO-2026-4315 - DoS via malicious p2p message affecting a vulnerable node in github.com/ethereum/go-ethereum](https://junglewise.ai/threats/cve-2026-22862-go-ethereum-is-vulnerable-to-dos-via-malicious-p2p-message)
- [GO-2026-4314 - High CPU usage leading to DoS via malicious p2p message in github.com/ethereum/go-ethereum](https://junglewise.ai/threats/cve-2026-22868-go-ethereum-is-vulnerable-to-high-cpu-usage-leading-to-dos-via)