risc0 vulnerable to arbitrary code execution in guest via memory safety failure in `sys_read`

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

RISC Zero is a zero-knowledge verifiable general computing platform based on zk-STARKs and the RISC-V microarchitecture. In versions 2.0.2 and below of risc0-zkvm-platform, when the zkVM guest calls sys_read, the host is able to use a crafted response to write to an arbitrary memory location in the guest. This capability can be leveraged to execute arbitrary code within the guest. As sys_read is the mechanism by which input is requested by the guest, all guest programs built with the affected versions are vulnerable. This critically compromises the soundness guarantees of the guest program. Other affected packages include risc0-aggregation versions below 0.9, risc0-zkos-v1compat below 2.1.0, risc0-zkvm versions between 3.0.0-rc.1 and 3.0.1. This issue has been fixed in the following versions: risc0-zkvm-platform 2.1.0, risc0-zkos-v1compat 2.1.0, risc0-aggregation 0.9, and risc0-zkvm 2.3.2 and 3.0.3.

Source published

1 Oct 2025 23:30:26 UTC

Source modified

2 Oct 2025 18:01:05 UTC

Observed here

23 Oct 2026 15:48:27 UTC

Source terms

CVE Program Terms of Use

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CVSS 4.0 · 9.3 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

RISC Zero is a zero-knowledge verifiable general computing platform based on zk-STARKs and the RISC-V microarchitecture. In versions 2.0.2 and below of risc0-zkvm-platform, when the zkVM guest calls sys_read, the host is able to use a crafted response to write to an arbitrary memory location in the guest. This capability can be leveraged to execute arbitrary code within the guest. As sys_read is the mechanism by which input is requested by the guest, all guest programs built with the affected versions are vulnerable. This critically compromises the soundness guarantees of the guest program. Other affected packages include risc0-aggregation versions below 0.9, risc0-zkos-v1compat below 2.1.0, risc0-zkvm versions between 3.0.0-rc.1 and 3.0.1. This issue has been fixed in the following versions: risc0-zkvm-platform 2.1.0, risc0-zkos-v1compat 2.1.0, risc0-aggregation 0.9, and risc0-zkvm 2.3.2 and 3.0.3.

Source published

Oct 1, 2025, 11:30:26 PM (timezone not stated)

Source modified

Oct 2, 2025, 6:01:05 PM (timezone not stated)

Observed here

7 Nov 2026 02:45:50 UTC

Source terms

ENISA EUVD · source terms and attribution apply

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: euvd · ENISA EUVD · source terms and attribution apply. Source text is retained; field grouping and change labels are provided by ChangeIntel.

EUVD CVSS 4.0 · 9.3 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

RISC Zero is a zero-knowledge verifiable general computing platform based on zk-STARKs and the RISC-V microarchitecture. In versions 2.0.2 and below of risc0-zkvm-platform, when the zkVM guest calls sys_read, the host is able to use a crafted response to write to an arbitrary memory location in the guest. This capability can be leveraged to execute arbitrary code within the guest. As sys_read is the mechanism by which input is requested by the guest, all guest programs built with the affected versions are vulnerable. This critically compromises the soundness guarantees of the guest program. Other affected packages include risc0-aggregation versions below 0.9, risc0-zkos-v1compat below 2.1.0, risc0-zkvm versions between 3.0.0-rc.1 and 3.0.1. This issue has been fixed in the following versions: risc0-zkvm-platform 2.1.0, risc0-zkos-v1compat 2.1.0, risc0-aggregation 0.9, and risc0-zkvm 2.3.2 and 3.0.3.

Source published

2 Oct 2025 00:15:49 UTC

Source modified

19 Oct 2026 17:10:00 UTC

Observed here

25 Oct 2026 03:17:27 UTC

Source terms

NIST NVD usage terms; underlying source attribution retained

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: nvd · NIST NVD usage terms; underlying source attribution retained. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 4.0 · [email protected] · Secondary · 9.3 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

# Arbitrary code execution in guest via memory safety failure in `sys_read` In affected versions of `risc0-zkvm-platform`, when the zkVM guest calls `sys_read`, the host is able to use a crafted response to write to an arbitrary memory location in the guest. This capability can be leveraged to execute arbitrary code within the guest. As `sys_read` is the mechanism by which input is requested by the guest, all guest programs built with the affected versions are vulnerable. This critically compromises the soundness guarantees of the guest program. A fix was applied in [\#3351](https://github.com/risc0/risc0/pull/3351). The vulnerable pointer arithmetic was removed, and replaced with a simplified implementation in the `v1compat` kernel which uses Rust’s slice functions to guarantee memory safety. The fix has been released as part of `risc0-zkvm` versions `2.3.2` and `3.0.3`. All prior versions are affected. ## Remediation All developers of zkVM applications should update their guests to use `risc0-zkvm` versions `^2.3.2` or `^3.0.3`. This upgrade can be accomplished by editing all `Cargo.toml` files in the following way. * Any references to [`risc0-zkvm`](https://crates.io/crates/risc0-zkvm) should use version specifiers `”2.3.2”` or `”3.0.3”`. * Any references to [`risc0-build`](https://crates.io/crates/risc0-build) should use version specifiers `”2.3.2”` or `”3.0.3”`, matching `risc0-zkvm`. * Any references to [`risc0-zkvm-platform`](https://crates.io/crates/risc0-zkvm-platform) should use version specifier `”2.1.0”` or later. Most projects will not have direct references to this crate. Rebuild your application including the guest. You can run the following command to check that the patch is applied: ```shell # Provide the path to your guest Cargo.toml. Should report risc0-zkvm-platform >=v2.1.0 cargo tree --depth 0 -p risc0-zkvm-platform --manifest-path path/to/methods/guest/Cargo.toml ``` Any applications that use the image ID of this guest need to be updated with the newly built image ID. Note that there are no changes to the RISC Zero proof system or circuits. Provers are not required to take any action. Users of the Groth16 smart contract verifier and the [RISC Zero Verifier Router](https://dev.risczero.com/api/blockchain-integration/contracts/verifier#verifier-router) are not required to take any action beyond updating their guest programs. Any applications using the `risc0-aggregation` crate or the `RiscZeroSetVerifier` smart contract should update to version `>=0.9`. This application includes a zkVM guest, which is vulnerable in versions prior to `0.9`. Instances of the `RiscZeroSetVerifier` operated by RISC Zero have been disabled via the estop mechanism outlined in the [Verifier Management Design](https://github.com/risc0/risc0-ethereum/blob/release-2.0/contracts/version-management-design.md#base-verifier-implementations).

Source published

1 Oct 2025 21:04:59 UTC

Source modified

10 Sep 2026 03:50:29 UTC

Observed here

24 Oct 2026 13:19:54 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V4 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Publisher rating · CRITICAL