Critical vulnerability in `ismp-grandpa` <v15.0.1

published 2025-01-28 21 mo ago modified 2026-06-17 4 mo ago also GHSA-wwx5-gpgr-vxr7 , EUVD-2025-0205

cvss: 9.3; version 4.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 26%
public exploits: 0; none known

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.

Patch / fix

fixed in 3 links 4

crates.io ismp-grandpa 15.0.1
crates.io grandpa-verifier-primitives 0.1.2
crates.io grandpa-verifier 0.1.2

github.com/polytope-labs/hyperbridge#372 commit
github.com/polytope-labs/ismp-substrate#64 commit
github.com/polytope-labs/ismp-substrate#64 commit
github.com/polytope-labs/ismp-substrate#64 commit

CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: 21 mo ago (2025-01-28)

Exploit prediction

0.33% chance of exploitation in the next 30 days, higher than 26% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	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
CNA	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/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

Affected packages

ecosystem	package	affected	fixed in
crates.io	ismp-grandpa	<15.0.1	15.0.1
crates.io	grandpa-verifier-primitives	<0.1.2	0.1.2
crates.io	grandpa-verifier	<0.1.2	0.1.2

Affected products

polytope-labs hyperbridge

Classification

Weakness

CWE-670 Always-Incorrect Control Flow Implementation
CWE-347 Improper Verification of Cryptographic Signature

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary