Summary
RISC Zero Ethereum invalid commitment with digest value of zero accepted by Steel.validateCommitment
Recommended actions
Users for the Steel Solidity library versions 2.1.0 or earlier should ensure they are using Steel.validateCommitment in tandem with zkVM proof verification of a Steel program, as shown in the ERC-20 counter example, and documentation. This is the correct usage of Steel, and users following this pattern are not at risk, and do not need to take action.
Users not verifying a zkVM proof of a Steel program should update their application to do so, as this is incorrect usage of Steel.
Credit
A thank you to Daniel526 on HackenProof for reporting this issue
Impact
Prior to 2.1.1 and 2.2.0, the Steel.validateCommitment Solidity library function will return true for a crafted commitment with a digest value of zero.
This violates the semantics of validateCommitment, as this does not commitment to a block that is in the current chain. Because the digest is zero, it does not correspond to any block and there exist no known openings. As a result, this commitment will never be produced by a correct zkVM guest using Steel. Leveraging this bug to compromise the soundness of an application using Steel would require a separate bug or misuse of the Steel library, which is expected to be used to validate the root of state opening proofs (e.g. having the guest commit to a digest of zero, or failing to check the zkVM proof).
Because this bug does not risk application integrity, correctly written applications are not at risk.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Already deployed Kodem?
See it in your environmentNew to Kodem? Get a demo →Remediation advice
Please see [#605] for a full description of the bug, and the fix. This fix has been released as part of risc0-ethereum [2.1.1] and [2.2.0].
Frequently Asked Questions
- What is CVE-2025-52884? CVE-2025-52884 is a low-severity security vulnerability in risc0-ethereum-contracts (rust), affecting versions < 2.1.1. It is fixed in 2.1.1.
- Which versions of risc0-ethereum-contracts are affected by CVE-2025-52884? risc0-ethereum-contracts (rust) versions < 2.1.1 is affected.
- Is there a fix for CVE-2025-52884? Yes. CVE-2025-52884 is fixed in 2.1.1. Upgrade to this version or later.
- Is CVE-2025-52884 exploitable, and should I be worried? Whether CVE-2025-52884 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2025-52884 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2025-52884? Upgrade
risc0-ethereum-contractsto 2.1.1 or later.