Is CVE-2026-96770 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-96770 being exploited in the wild.

How severe is CVE-2026-96770?

Informational severity, published 23 September 2026.

Which products and versions are affected?

Temporal S2s-Proxy 0.1.16 through 0.2.2.

Is there a fix for CVE-2026-96770?

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-2026-96770 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-96770?

Check whether you run Temporal S2s-Proxy 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.

CVE-2026-96770: s2s-proxy TLS client certificate verification bypass

CVE-2026-96770 · Severity: info · Published 2026-09-23

s2s-proxy is a service-to-service proxy for Temporal workflow systems that secures connections between services. Versions up to 0.2.2 improperly validate TLS client certificates, allowing attackers to connect with self-signed certificates and invoke proxied RPC calls without legitimate credentials. An attacker can bypass authentication controls and access Temporal workflows and data without authorization.

Vendors: Temporal.

Quick answers

Is CVE-2026-96770 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-96770 being exploited in the wild.
How severe is CVE-2026-96770?: Informational severity, published 23 September 2026.
Which products and versions are affected?: Temporal S2s-Proxy 0.1.16 through 0.2.2.
Is there a fix for CVE-2026-96770?: 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-2026-96770 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-96770?: Check whether you run Temporal S2s-Proxy 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

In s2s-proxy versions 0.1.16 through 0.2.2, TLS server listeners configured with skipCAVerification=false incorrectly use Go's RequireAnyClientCert mode, which verifies certificate possession but does not validate the certificate against the configured CA. An attacker can establish a TLS connection using any self-signed certificate, then invoke RPC methods allowed by the proxy's configuration and gain unauthorized access to Temporal credentials and workflows. The vulnerability is a certificate validation bypass requiring only network access to the proxy's TLS listener.

Affected products

Temporal s2s-proxy 0.1.16 through 0.2.2

Timeline

2026-09-23: disclosed

References

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