# CVE-2026-65654: Temporal ringpop-go insufficient label validation in SWIM membership

Source: https://junglewise.ai/threats/cve-2026-65654-github-com-temporalio-ringpop-go-enforces-configured-labeloptions  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-21. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-65654 · Severity: info · Published 2026-09-21

Temporal's ringpop-go library provides distributed membership management via the SWIM gossip protocol. A network peer can send malicious label updates that bypass configured size limits, causing memory exhaustion and bandwidth waste that may crash the process. Only availability is affected; no data confidentiality or integrity risk was identified.

Vendors: [Temporal](https://junglewise.ai/threats/vendors/temporal).

## Quick answers

**Is CVE-2026-65654 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-65654 being exploited in the wild.

**How severe is CVE-2026-65654?** Informational severity, published 21 September 2026.

**Which products and versions are affected?** Temporal Ringpop-Go versions prior to fix (exact version not specified).

**Is there a fix for CVE-2026-65654?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-65654 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-65654?** Check whether you run Temporal Ringpop-Go at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The SWIM membership protocol enforces label key/value/count size limits on locally-set labels but fails to validate the same limits on labels received from peer nodes during membership updates. An unauthenticated network peer reaching the TChannel listener can repeatedly submit labels exceeding configured LabelOptions limits, which are retained in the member list and re-gossiped, allowing resource consumption to exceed bounds. The fix adds validation of peer-supplied label maps before retention or dissemination.

## Affected products

- Temporal ringpop-go versions prior to fix (exact version not specified)

## Timeline

- 2026-09-21: disclosed

## References

- [https://pkg.go.dev/](https://pkg.go.dev/)
- [https://github.com/temporalio/ringpop-go/blob/b97329e994f792f70427a7533a3e7a98976eb262/swim/labels.go](https://github.com/temporalio/ringpop-go/blob/b97329e994f792f70427a7533a3e7a98976eb262/swim/labels.go)