GHSA-f6rc-24x4-ppxp
RISC Zero Underconstrained Vulnerability: Division
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
risc0-zkvm🦀risc0-circuit-rv32im🦀risc0-circuit-rv32im-sysReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects crates.io packages — download data is not available via public APIs for these ecosystems.
Description
Two issues were found: For some inputs to signed integer division, the circuit allowed two outputs, only one of which was valid. Additionally, the result of division by zero was underconstrained.
This vulnerability was identified using the Picus tool from Veridise.
Impacted on-chain verifiers have already been disabled via the estop mechanism outlined in the Verifier Management Design.
Mitigation
We recommend all impacted users upgrade as soon as possible.
Rust applications using the risc0-zkvm crate at versions < 2.2 should upgrade to version 2.2.0 or later.
Smart contract applications using the official RISC Zero Verifier Router do not need to take any action: zkVM version 2.2 is active on all official routers, and version 2.1 has been disabled.
Smart contract applications not using the verifier router should update their contracts to send verification calls to the 2.2 version of the verifier.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | risc0-zkvm | ≥ 2.0.0&&< 2.2.0 | 2.2.0 |
| 🦀crates.io | risc0-circuit-rv32im | ≥ 2.0.0&&< 3.0.0 | 3.0.0 |
| 🦀crates.io | risc0-circuit-rv32im-sys | ≥ 2.0.0&&< 3.0.0 | 3.0.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for risc0-zkvm. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update risc0-zkvm to 2.2.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-f6rc-24x4-ppxp is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-f6rc-24x4-ppxp is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-f6rc-24x4-ppxp. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-f6rc-24x4-ppxp in your dependencies?
O3 detects GHSA-f6rc-24x4-ppxp across crates.io dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.