# CVE-2026-52879: Klever-Go: Unbounded goroutine spawn on direct-message ingress enables peer-driven DoS

> A remote attacker can cause denial of service in Klever-Go nodes by sending direct messages that trigger unbounded goroutine creation, exhausting system resources.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 7 Aug 2026
- **Updated:** 10 Aug 2026
- **Also known as:** GHSA-hf2g-6j7h-98wg, GO-2026-5424

## What is CVE-2026-52879?

CVE-2026-52879 is a high-severity denial of service vulnerability in klever-io klever-go, published on 7 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Klever-Go is the Go implementation of the Klever blockchain protocol. In versions 1.7.14 through 1.7.17, the direct-message ingress handler spawns a new goroutine for every incoming direct message before the processor-level antiflood layer makes any admission decision, with no semaphore, throttler, or bound on the number of concurrent in-flight spawns. Because the antiflood check runs inside the spawned goroutine rather than before it, a single connected peer can open a direct-send stream and send a stream of well-formed messages to force unbounded goroutine creation, where each goroutine allocates its own stack and holds a message reference until processing completes, adding scheduler and garbage-collection pressure faster than the runtime can drain it. This lets one peer degrade the node's availability and its ability to process legitimate traffic, resulting in a remotely triggerable denial of service. The issue is fixed in 1.7.18.

Weakness: CWE-770 (Allocation of Resources Without Limits or Throttling), CWE-400 (Uncontrolled Resource Consumption)

## Which versions are affected by CVE-2026-52879?

3 open source packages ship an affected version, including github.com/klever-io/klever-go.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/klever-io/klever-go` | Go | From 1.7.14 | 1.7.18 |
| `github.com/klever-io/klever-go` | Go | From 1.7.14 | 1.7.18 |
| `github.com/klever-io/klever-go` | Go | From 1.7.14 | 1.7.18 |

## How do I fix CVE-2026-52879?

Upgrade github.com/klever-io/klever-go to 1.7.18 or later.

## Is CVE-2026-52879 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-52879 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-52879 and fix it if it is affected.

What it is: CVE-2026-52879 is a high-severity denial of service vulnerability in klever-io klever-go, published on 7 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-52879 exists.

Affected packages and fixed versions:
- github.com/klever-io/klever-go (Go): affected from 1.7.14; fixed in 1.7.18
- github.com/klever-io/klever-go (Go): affected from 1.7.14; fixed in 1.7.18
- github.com/klever-io/klever-go (Go): affected from 1.7.14; fixed in 1.7.18

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-52879/ (Markdown: https://insights.sbomify.com/CVE-2026-52879/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-52879
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-52879
- OSV: https://osv.dev/vulnerability/CVE-2026-52879

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-52879/
Summaries are generated and may contain mistakes; the official description above is the record.