CVE-2026-96770 (GCVE-0-2026-96770)
Vulnerability from cvelistv5
Published
2026-09-23 18:58
Modified
2026-09-23 19:36
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-296 - Improper Following of a Certificate's Chain of Trust
Summary
All published s2s-proxy versions through 0.2.2 are affected. In versions 0.1.16 through 0.2.2, TLS server listeners use Go's RequireAnyClientCert mode when skipCAVerification is false. This mode checks that the client holds the certificate's private key but does not verify the certificate against the configured CA. An attacker can therefore use a self-signed certificate and key to establish a TLS and yamux connection, then invoke RPCs allowed by the proxy's configuration and Temporal credentials. No certificate or private key trusted by the deployment, and no Temporal credential, is required.
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| Temporal Technologies, Inc. | s2s-proxy |
Version: 0.0.1-alpha ≤ 0.2.2 |
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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