# CVE-2026-97055: SigNoz JWT tokenizer authentication bypass via empty signing secret

Source: https://junglewise.ai/threats/cve-2026-97055-signoz-from-v0-8-0-before-v0-143-0-defaults-the-jwt-tokenizer  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-24. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-97055 · Severity: high · CVSS 8.1 · Published 2026-09-24

SigNoz is an open-source application performance monitoring platform used for tracing and observability. Versions 0.8.0 through 0.142.x default the JWT signing secret to an empty string, allowing an attacker to forge valid session tokens for any user, including administrators, without authentication. An attacker can impersonate users and maintain access via refresh tokens that cannot be revoked.

Technologies: [Signoz](https://junglewise.ai/threats/technologies/signoz). Vendors: [SigNoz](https://junglewise.ai/threats/vendors/signoz).

## Quick answers

**Is CVE-2026-97055 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-97055 being exploited in the wild.

**How severe is CVE-2026-97055?** High severity, with a CVSS score of 8.1, published 24 September 2026.

**Which products and versions are affected?** Signoz v0.8.0 through v0.142.x.

**Is there a fix for CVE-2026-97055?** A patch was published on 2026-09-24: Fixed in v0.143.0 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-97055 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-97055?** Check whether you run Signoz 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

The JWT tokenizer in SigNoz uses an empty HMAC key when SIGNOZ_TOKENIZER_JWT_SECRET is not configured, enabling unauthenticated attackers to forge valid session tokens by signing claims with the empty key. The vulnerability requires knowledge of a user ID (which can be obtained from the unauthenticated /api/v2/sessions/context endpoint) and allows forged refresh tokens to be exchanged for new token pairs with 30-day validity. The fix requires JWT secrets at startup and changes the default tokenizer provider to opaque.

## Affected products

- SigNoz SigNoz v0.8.0 through v0.142.x

## Timeline

- 2026-09-24: disclosed: Vulnerability published
- 2026-09-24: patched: Fixed in v0.143.0

## References

- [https://github.com/SigNoz/signoz/commit/67895d366d](https://github.com/SigNoz/signoz/commit/67895d366d)
- [https://github.com/SigNoz/signoz/commit/b02aae2db3](https://github.com/SigNoz/signoz/commit/b02aae2db3)

## Related threats

- [SigNoz session token revocation bypass on password reset and user deletion](https://junglewise.ai/threats/cve-2026-97056-signoz-versions-from-v0-98-0-up-to-but-not-including-v0-143-0)
- [SigNoz SQL injection in query_range API field-key names](https://junglewise.ai/threats/cve-2026-93426-signoz-sql-injection-in-query-range-api-field-key-names)
- [SigNoz SQL injection in trace-funnel analytics](https://junglewise.ai/threats/cve-2026-93292-signoz-sql-injection-in-trace-funnel-analytics)
- [SigNoz authorization bypass in trace-funnel analytics endpoints](https://junglewise.ai/threats/cve-2026-92729-signoz-authorization-bypass-in-trace-funnel-analytics-endpoints)
- [SigNoz open redirect and session token theft in SSO flow](https://junglewise.ai/threats/cve-2026-63094-signoz-open-redirect-and-session-token-theft-in-sso-flow)