Klever-Go MultiDataInterceptor: remote OOM via crafted compressed P2P payload

published 2026-05-13 5 mo ago modified 2026-07-21 3 mo ago also GHSA-87m7-qffr-542v , GO-2026-5246 , EUVD-2026-33375

cvss: 8.6; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 34%
public exploits: 0; none known

Klever-Go is the Go implementation of the Klever blockchain protocol. Prior to 1.7.17, a remote, unauthenticated denial-of-service vulnerability in Batch.Decompress (data/batch/batch.go) allows any peer that participates in a topic served by MultiDataInterceptor to allocate multi-gigabyte heaps on the receiving node from a sub-50 KiB gossip payload. A single packet is sufficient to OOM-kill a validator with conventional memory provisioning. Fleet-wide application affects chain liveness. This vulnerability is fixed in 1.7.17.

Patch / fix

distros 1

govulncheck-vulndb openSUSE Leap 16.0 0.0.20260723T184607-160000.1.1

opensuse advisories openSUSE-SU-2026:21483-1

CISA SSVC

Exploitation: Proof of concept is public
Automatable: yes
Technical impact: partial
Assessed: 5 mo ago (2026-06-02)

Exploit prediction

0.40% chance of exploitation in the next 30 days, higher than 34% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/klever-io/klever-go/security/advisories/GHSA-87m7-qffr-542v referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	3.1	8.6	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
GitHub	3.1	8.6	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Affected packages

ecosystem	package	affected	fixed in
go	github.com/klever-io/klever-go	<=1.7.16 all versions	no fix listed

Affected products

klever-io klever-go

Classification

Weakness

CWE-409 Improper Handling of Highly Compressed Data (Data Amplification)
CWE-770 Allocation of Resources Without Limits or Throttling

References

github.com /klever-io/klever-go/security/advisories/GHSA-87m7-qffr-542v
exploit, web, advisory
nvd.nist.gov /vuln/detail/CVE-2026-44697
advisory
github.com /klever-io/klever-go
package

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