CVE-2025-24800
Critical vulnerability in `ismp-grandpa` <v15.0.1
Hyperbridge is a hyper-scalable coprocessor for verifiable, cross-chain interoperability. A critical vulnerability was discovered in the ismp-grandpa crate, that allowed a malicious prover easily convince the verifier of the finality of arbitrary headers. This could be used to steal funds or compromise other kinds of cross-chain applications. This vulnerability is fixed in 15.0.1.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Critical vulnerability in `ismp-grandpa` <v15.0.1
Hyperbridge is a hyper-scalable coprocessor for verifiable, cross-chain interoperability. A critical vulnerability was discovered in the ismp-grandpa crate, that allowed a malicious prover easily convince the verifier of the finality of arbitrary headers. This could be used to steal funds or compromise other kinds of cross-chain applications. This vulnerability is fixed in 15.0.1.
- Record
CVE-2025-24800- CVSS 4.0
- 9.3 Critical
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 - Weakness
- CWE-670, CWE-347
- Updated
- 2026-11-02
EUVDEUVD-2025-0205
Hyperbridge is a hyper-scalable coprocessor for verifiable, cross-chain interoperability. A critical vulnerability was discovered in the ismp-grandpa crate, that allowed a malicious prover easily convince the verifier of the finality of arbitrary headers. This could be used to steal funds or compromise other kinds of cross-chain applications. This vulnerability is fixed in 15.0.1.
- Record
EUVD-2025-0205- CVSS 4.0
- 9.3 Critical
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 - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-wwx5-gpgr-vxr7
ismp-grandpa crate accepted incorrect signatures
A critical vulnerability was discovered in the ismp-grandpa crate, that allowed a malicious prover easily convince the verifier of the finality of arbitrary headers.
Description
The vulnerability manifests as a verifer that only accepts incorrect signatures of Grandpa precommits and was introduced in this specific commit. Perhaps due to unfamiliarity with core substrate APIs. The if statement should have included a negation check, similar to the previous code, but this was omitted. Causing the verifier to only accept invalid signatures.
This vulnerability remained undetected even with integration tests, as the prover was also misconfigured to initialize the Grandpa verifier with the incorrect authority set_id. This causes verification of honest precommit signatures to fail as the message is now malformed, but the verifier indeed only accepts signatures or messages that fail the verification check.
But even more devastatingly, the verifier will also accept malicious GRANDPA signatures for any precommit message.
This vulnerability has been fixed in this commit and a patch release has been published.
Impact
This could be used to steal funds or compromise other kinds of cross-chain applications.
Patches
This vulnerability has been fixed in the latest version of ismp-granpda v15.0.1
Recommendations
Users who rely on the compromised versions must upgrade immediately, as all vulnerable versions of the crate has been yanked.
- Record
GHSA-wwx5-gpgr-vxr7- CVSS 4.0
- 9.3 Critical
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N - Weakness
- CWE-347
- Updated
- 2026-11-02
NVD
Hyperbridge is a hyper-scalable coprocessor for verifiable, cross-chain interoperability. A critical vulnerability was discovered in the ismp-grandpa crate, that allowed a malicious prover easily convince the verifier of the finality of arbitrary headers. This could be used to steal funds or compromise other kinds of cross-chain applications. This vulnerability is fixed in 15.0.1.
- Record
CVE-2025-24800- CVSS 4.0
- 9.3 Critical
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 - Weakness
- CWE-347, CWE-670
- Updated
- 2026-11-02
OSV
Critical vulnerability in `ismp-grandpa` <v15.0.1
Hyperbridge is a hyper-scalable coprocessor for verifiable, cross-chain interoperability. A critical vulnerability was discovered in the ismp-grandpa crate, that allowed a malicious prover easily convince the verifier of the finality of arbitrary headers. This could be used to steal funds or compromise other kinds of cross-chain applications. This vulnerability is fixed in 15.0.1.
- Record
CVE-2025-24800- CVSS 4.0
- 9.3 Critical
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 - Weakness
- CWE-347, CWE-670
- Updated
- 2026-11-02
OSVGHSA-wwx5-gpgr-vxr7
ismp-grandpa crate accepted incorrect signatures
A critical vulnerability was discovered in the ismp-grandpa crate, that allowed a malicious prover easily convince the verifier of the finality of arbitrary headers.
Description
The vulnerability manifests as a verifer that only accepts incorrect signatures of Grandpa precommits and was introduced in this specific commit. Perhaps due to unfamiliarity with core substrate APIs. The if statement should have included a negation check, similar to the previous code, but this was omitted. Causing the verifier to only accept invalid signatures.
This vulnerability remained undetected even with integration tests, as the prover was also misconfigured to initialize the Grandpa verifier with the incorrect authority set_id. This causes verification of honest precommit signatures to fail as the message is now malformed, but the verifier indeed only accepts signatures or messages that fail the verification check.
But even more devastatingly, the verifier will also accept malicious GRANDPA signatures for any precommit message.
This vulnerability has been fixed in this commit and a patch release has been published.
Impact
This could be used to steal funds or compromise other kinds of cross-chain applications.
Patches
This vulnerability has been fixed in the latest version of ismp-granpda v15.0.1
Recommendations
Users who rely on the compromised versions must upgrade immediately, as all vulnerable versions of the crate has been yanked.
- Record
GHSA-wwx5-gpgr-vxr7- CVSS 4.0
- 9.3 Critical
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N - Weakness
- CWE-347
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
ismp-grandpacrates.io |
before 15.0.1 | 15.0.1 |
grandpa-verifier-primitivescrates.io |
before 0.1.2 | 0.1.2 |
grandpa-verifiercrates.io |
before 0.1.2 | 0.1.2 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, published | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2025-24800 is a critical vulnerability (CVSS 9.3) in Polytope-labs Hyperbridge, published January 28, 2025. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.33%, the 26th percentile. Fixed in ismp-grandpa 15.0.1.
References
github.com/polytope-labs/hyperbridge/security/advisories/GHSA-wwx5-gpgr-vxr7
nvd.nist.gov/vuln/detail/CVE-2025-24800