How severe is CVE-2026-65654?

CVE-2026-65654 has a CVSS 4.0 base score of 8.7, rated high severity.

Is CVE-2026-65654 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-65654?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2026-65654 published?

CVE-2026-65654 was published on 2026-09-21 and last updated on 2026-09-22.

CVE-2026-65654

CVE-2026-65654 is a high-severity vulnerability with a CVSS 4.0 base score of 8.7. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-770.

Key facts

Severity: High (CVSS 4.0 base score 8.7)
EPSS exploit prediction: 1% (46th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-770
Published: 2026-09-21
Last modified: 2026-09-22

Description

github.com/temporalio/ringpop-go enforces configured LabelOptions limits when an application changes the local node's labels, but affected versions do not apply those limits to label maps received in SWIM membership changes. A network peer that can reach a live Ringpop TChannel listener can repeatedly submit changes for distinct member addresses containing label keys, values, or counts that exceed the receiver's configured limits. Accepted labels are retained in the member list and disseminated to peers, allowing memory and gossip-bandwidth consumption to exceed configured bounds and potentially making the hosting process unavailable. The fix validates peer-supplied label maps before they are retained or disseminated. Availability only; no confidentiality or integrity impact was identified.

Frequently asked questions

What is CVE-2026-65654?: github.com/temporalio/ringpop-go enforces configured LabelOptions limits when an application changes the local node's labels, but affected versions do not apply those limits to label maps received in SWIM membership changes. A network peer that can reach a live Ringpop TChannel listener can repeatedly submit changes for distinct member addresses containing label keys, values, or counts that exceed the receiver's configured limits. Accepted labels are retained in the member list and disseminated to peers, allowing memory and gossip-bandwidth consumption to exceed configured bounds and potentially making the hosting process unavailable. The fix validates peer-supplied label maps before they are retained or disseminated. Availability only; no confidentiality or integrity impact was identified.
How severe is CVE-2026-65654?: CVE-2026-65654 has a CVSS 4.0 base score of 8.7, rated high severity.
Is CVE-2026-65654 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-65654?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2026-65654 published?: CVE-2026-65654 was published on 2026-09-21 and last updated on 2026-09-22.

References

Other CWE-770 (Allocation of Resources Without Limits or Throttling) vulnerabilities

CVE-2026-63299 — Critical (CVSS 9.9): An authorization bypass vulnerability in LXD allows an authenticated user to bypass project-level disk and volume…
CVE-2026-82439 — Critical (CVSS 9.8): Description The DRPC server kept a map from function name to request queue and created an entry the first time…
CVE-2026-47891 — Critical (CVSS 9.8): A Spring WebFlux application that relies on the Aalto XML processor to parse XML input does not correctly enforce the…
CVE-2026-74878 — Critical (CVSS 9.8): openssl_encrypt versions before 1.4.0 use an in-memory rate limiter for TOTP brute-force protection that is not shared…
CVE-2026-31283 — Critical (CVSS 9.8): In Totara LMS v19.1.5 and before, the forgot password API does not implement rate limiting for the target email…
CVE-2020-37067 — Critical (CVSS 9.8): Filetto 1.0 FTP server contains a denial of service vulnerability in the FEAT command processing that allows attackers…

Browse all CWE-770 (Allocation of Resources Without Limits or Throttling) vulnerabilities →