Live Exposure Defense: From CVE to Confirmed Exposure in 12 Hours – See more

Back
New CVE Detected

CVE-2026-97055 – Authentication Bypass via Empty JWT Secret – SigNoz v0.8.0–v0.142.1

Be the first to know when new zero-days emerge:

Subscribe to Email Alerts
Subscribe to RSS Feed

Summary

CVE-2026-97055 is a critical authentication bypass vulnerability in SigNoz, an open-source observability platform, caused by the JWT tokenizer defaulting to an empty signing secret that is never validated at startup. Any deployment that does not explicitly configure a JWT secret signs and verifies session tokens with an empty HMAC key, letting an attacker forge valid session tokens for any existing user — including administrators — without credentials. The issue carries a CVSS v4.0 score of 9.2 (Critical), reflecting full compromise of confidentiality, integrity, and availability over the network.

Technical details

  • Root cause: the tokenizer configuration parameters SIGNOZ_TOKENIZER_JWT_SECRET (and the deprecated SIGNOZ_JWT_SECRET) default to an empty string (""), and SigNoz’s validation logic fails to reject this insecure default before signing/verifying tokens.
  • Trigger condition: the flaw is present on any SigNoz instance running the default (opaque-less) JWT tokenizer without an explicitly configured, non-empty signing secret.
  • Attack chain: an attacker obtains a target user ID (from logs, URLs, or token payloads) and the organization ID via the unauthenticated /api/v2/sessions/context endpoint, then crafts a JWT signed with the known-empty HMAC key to impersonate that user.
  • Attack vector: fully remote and unauthenticated over the network (AV:N); exploitation requires no user interaction.
  • Impact: forged access and refresh tokens grant full account takeover, including admin impersonation and complete control over the SigNoz instance. Forged refresh tokens cannot be revoked and remain valid for their default 30-day lifetime, enabling persistent, long-lived unauthorized access to all stored telemetry (traces, logs, metrics) and configuration data.

Affected software

  • SigNoz versions v0.8.0 through v0.142.1 (inclusive) using the default JWT tokenizer without a manually configured, non-empty signing secret.
  • Fixed in v0.143.0, which defaults to an opaque tokenizer with proper validation.

Severity

  • CVSS v3.1 Base Score: 8.1 (High) — CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
  • CVSS v4.0 Score: 9.2 (Critical) — CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Mitigation and recommended actions

  • Immediate: Upgrade SigNoz to v0.143.0 or later, which replaces the vulnerable default tokenizer with an opaque tokenizer that enforces validation of the signing secret.
  • If immediate patching is not possible: explicitly set SIGNOZ_TOKENIZER_JWT_SECRET to a strong, randomly generated value (do not leave it unset or empty) and restart the service so all previously issued tokens are invalidated.
  • Additionally, restrict network exposure of the SigNoz management interface and API endpoints (including /api/v2/sessions/context) to trusted networks where possible, and rotate any credentials/tokens issued prior to remediation.

References

Are you exposed?

Get a free report of your organization’s exposure to this CVE and threat

  • Mapping of all Assets with this Technology
  • Identification of potentially exposed assets to this CVE
  • Confirmation of verified exploitable assets
Get Exposure Report

How IONIX’s External Exposure Management Platform Detects and Validates
Zero-Days to Shrink MTTR

1

Map your entire attack surface (continously)

IONIX uses multi-factor discovery methods, including DNS analysis, certificate mapping, metadata inspection, and more, to automatically map every internet-facing asset across your environment. This includes cloud instances, third-party platforms, shadow IT, and even forgotten infrastructure that traditional tools miss.

2

Monitor for new CVEs

Dozens of threat intel feeds using agentic technology are continuously analyzed to detect the appearance of proof-of-concept code, exploit kits, and indicators of active targeting. IONIX goes further by applying AI to proactively evaluate whether emerging vulnerabilities are likely to be exploited, even before PoCs go public.

3

Identify Potential External Exposures

Not all CVEs matter. IONIX filters vulnerabilities by asking attacker-centric questions: Can it be reached from the internet? Does it require authentication? Is it being exploited in the wild? This dramatically reduces noise and focuses teams on threats that can actually be weaponized.

4

Create Safe, Scalable Exploit Validations

IONIX transforms real-world PoCs into safe, non-intrusive test payloads that can be run in production environments without disruption. These simulations are precisely targeted to the systems that are vulnerable, ensuring rapid validation without unnecessary load.

5

Execute Exploit Validations

By combining context about software stack, versioning, exposure status, and reachability, IONIX ensures that only the right payloads are executed against the right assets, maximizing efficiency and minimizing risk.

6

Drive Fast and Actionable Remediation

Results are routed through integrations with ticketing, SOAR, and SIEM tools. Issues are written in plain language, bundled into remediation clusters, and prioritized based on asset criticality, exploitability, and blast radius. This shortens mean time to remediation (MTTR) and empowers teams to act with confidence.

Are you exposed?

Get a free report of your organization’s exposure to this CVE and threat

  • Mapping of all Assets with this Technology
  • Identification of potentially exposed assets to this CVE
  • Confirmation of verified exploitable assets
Get Exposure Report
Close

Subscribe to Threat Center RSS

Copy/paste the link below into your preferred RSS reader or follow these instructions to subscribe to Slack alerts.

Open RSS feedSlack setup instructions

Close

Get Real-Time CVE Alerts to Your Email

Be the first to know when new zero-days emerge