risc0 RISC Zero up to 2.0.x sys_read code injection

Summaryinfo

A vulnerability was found in risc0 RISC Zero up to 2.0.x and classified as critical. This affects the function sys_read. Executing a manipulation can lead to code injection. This vulnerability is registered as CVE-2025-61588. It is possible to launch the attack remotely. No exploit is available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in risc0 RISC Zero up to 2.0.x. It has been declared as very critical. This vulnerability affects the function sys_read. The manipulation with an unknown input leads to a code injection vulnerability. The CWE definition for the vulnerability is CWE-94. The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is shared for download at github.com. This vulnerability was named CVE-2025-61588 since 09/26/2025. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 10/02/2025). The MITRE ATT&CK project declares the attack technique as T1059.

Upgrading to version 2.1.0 eliminates this vulnerability. Applying the patch 3f00e1fa0159599c1601e788021f2169d1f0a4dc is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2025-32056). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Vendor

• risc0

Name

• RISC Zero

Version

• 2.0

License

• open-source

CPE 2.3info

• 🔒

CPE 2.2info

• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Discussion