CVE-2025-30215: NATS Server may fail to authorize certain Jetstream admin APIs

Should you act?

Critical, preconditions apply

Severe if exploited, but exploitation needs conditions that may not apply to you. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

• Not in CISA KEV, but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
• EPSS 0.6%, percentile 48: FIRST’s model estimates a 0.6% chance of exploitation activity in the next 30 days, higher than 48% of all scored CVEs (low). EPSS is a probability, not a verdict.
• Needs an account (low (any account)). Exposure depends on who can log in.
• Only applies if your dependency tree includes github.com/nats-io/nats-server/v2 (Go) >= 2.11.0-RC.1, < 2.11.1, fixed in 2.11.1; github.com/nats-io/nats-server/v2 (Go) >= 2.2.0, < 2.10.27, fixed in 2.10.27. Check your lockfile, including transitive dependencies.

What it is

NATS-Server is a High-Performance server for NATS.io, the cloud and edge native messaging system. In versions starting from 2.2.0 but prior to 2.10.27 and 2.11.1, the management of JetStream assets happens with messages in the $JS. subject namespace in the system account; this is partially exposed into regular accounts to allow account holders to manage their assets. Some of the JS API requests were missing access controls, allowing any user with JS management permissions in any account to perform certain administrative actions on any JS asset in any other account. At least one of the unprotected APIs allows for data destruction. None of the affected APIs allow disclosing stream contents. This vulnerability is fixed in v2.11.1 or v2.10.27.

From the GitHub advisory

Advisory

The management of JetStream assets happens with messages in the $JS. subject namespace in the system account; this is partially exposed into regular accounts to allow account holders to manage their assets.

Some of the JS API requests were missing access controls, allowing any user with JS management permissions in any account to perform certain administrative actions on any JS asset in any other account. At least one of the unprotected APIs allows for data destruction. None of the affected APIs allow disclosing stream contents.

Affected versions

NATS Server: Version 2 from v2.2.0 onwards, prior to v2.11.1 or v2.10.27

Weakness type: CWE-306, CWE-287, CWE-285.

Product: github.com/nats-io/nats-server/v2 (Go) · Assigned by: GitHub_M · Published: 2025-04-15

Affected and fixed versions

Severity scores

• Attack vector: network (remotely reachable)
• Attack complexity: low
• Privileges required: low (any account)
• User interaction: none
• Scope: changed (can affect other components)

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

• CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
• CISA SSVC assessment: exploitation poc, automatable no, technical impact partial.
• FIRST EPSS (model of 2026-10-21): 0.60% probability of exploitation activity in the next 30 days; percentile 48.

Timeline

• 2025-04-15 — CVE record published by GitHub_M
• 2025-04-15 — GitHub-reviewed advisory GHSA-fhg8-qxh5-7q3w published (critical)
• 2025-04-17 — CVE record last updated

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vulnerability records

1. GitHub Advisory GHSA-fhg8-qxh5-7q3w github.com
2. CVE.org record CVE-2025-30215 cve.org
3. NVD entry CVE-2025-30215 nvd.nist.gov

Other references from the CVE record and advisory

1. github.com github.com
2. advisories.nats.io advisories.nats.io
3. openwall.com openwall.com
4. osv.dev osv.dev
5. github.com github.com

Critical Go advisories · Today’s Security Digest