CVE-2026-108126 temporal-proxy payload decryption is not bound to the request namespace
Attackers with access to one namespace can decrypt payloads from another namespace via the temporal-proxy, leading to unauthorized data disclosure.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-108126?
CVE-2026-108126 is a medium-severity missing authorization vulnerability in temporal-proxy, published on 15 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
temporal-proxy 0.2.0 through 0.8.0 does not bind encrypted payloads to the namespace they were encrypted for. When payload encryption is enabled, the proxy chooses the decryption key by an identifier stored in the payload rather than by the namespace of the request, and nothing in the ciphertext records that namespace. A caller whom the proxy authorizes only for namespace B, and who has obtained an encrypted payload from namespace A, can therefore have the proxy decrypt it. In 0.8.0, the caller can submit the payload to the codec server's /decode endpoint. In every affected version, a caller who can also write to namespace B on the Temporal server directly can place the payload there and read it back through the proxy. This holds whether namespaces share the default key or each has its own, because a single proxy holds every key it is configured with. The issue does not give the attacker encrypted payloads they could not already obtain, and does not allow encrypted payloads to be modified.
Weakness: CWE-639
Which versions are affected by CVE-2026-108126?
How do I fix CVE-2026-108126?
No fix has been published for CVE-2026-108126 yet. Limit exposure of the affected software until one is available.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-108126 being exploited?
There is no known exploitation of CVE-2026-108126 in the wild and no public exploit code.
Sources
Also known as GHSA-vm4x-rqwp-c27m.