CVE-2026-58250
NATS Server: Pre-auth server crash via double INFO in leafnode handshake
NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.12.8 and 2.11.17, an unauthenticated peer with network access to a leafnode listener with compression enabled could crash the server during the pre-authentication leafnode handshake by sending repeated leafnode INFO protocol messages before authentication and account setup completed. This issue is fixed in versions 2.12.8 and 2.11.17.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
NATS Server: Pre-auth server crash via double INFO in leafnode handshake
NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.12.8 and 2.11.17, an unauthenticated peer with network access to a leafnode listener with compression enabled could crash the server during the pre-authentication leafnode handshake by sending repeated leafnode INFO protocol messages before authentication and account setup completed. This issue is fixed in versions 2.12.8 and 2.11.17.
- Record
CVE-2026-58250- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-476
- Updated
- 2026-11-02
EUVDEUVD-2026-42380
NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.12.8 and 2.11.17, an unauthenticated peer with network access to a leafnode listener with compression enabled could crash the server during the pre-authentication leafnode handshake by sending repeated leafnode INFO protocol messages before authentication and account setup completed. This issue is fixed in versions 2.12.8 and 2.11.17.
- Record
EUVD-2026-42380- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
NVD
NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.12.8 and 2.11.17, an unauthenticated peer with network access to a leafnode listener with compression enabled could crash the server during the pre-authentication leafnode handshake by sending repeated leafnode INFO protocol messages before authentication and account setup completed. This issue is fixed in versions 2.12.8 and 2.11.17.
- Record
CVE-2026-58250- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-476
- Updated
- 2026-11-02
OSV
NATS Server: Pre-auth server crash via double INFO in leafnode handshake
NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.12.8 and 2.11.17, an unauthenticated peer with network access to a leafnode listener with compression enabled could crash the server during the pre-authentication leafnode handshake by sending repeated leafnode INFO protocol messages before authentication and account setup completed. This issue is fixed in versions 2.12.8 and 2.11.17.
- Record
CVE-2026-58250- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-476
- Updated
- 2026-11-02
OSVDEBIAN-CVE-2026-58250
NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.12.8 and 2.11.17, an unauthenticated peer with network access to a leafnode listener with compression enabled could crash the server during the pre-authentication leafnode handshake by sending repeated leafnode INFO protocol messages before authentication and account setup completed. This issue is fixed in versions 2.12.8 and 2.11.17.
- Record
DEBIAN-CVE-2026-58250- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVJLSEC-2026-1150
NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.12.8 and 2.11.17, an unauthenticated peer with network access to a leafnode listener with compression enabled could crash the server during the pre-authentication leafnode handshake by sending repeated leafnode INFO protocol messages before authentication and account setup completed. This issue is fixed in versions 2.12.8 and 2.11.17.
- Record
JLSEC-2026-1150- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-58250
NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.12.8 and 2.11.17, an unauthenticated peer with network access to a leafnode listener with compression enabled could crash the server during the pre-authentication leafnode handshake by sending repeated leafnode INFO protocol messages before authentication and account setup completed. This issue is fixed in versions 2.12.8 and 2.11.17.
- Record
UBUNTU-CVE-2026-58250- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVAZL-92250 No score
CVE-2026-58250 affecting package telegraf for versions less than 1.31.0-27
NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.12.8 and 2.11.17, an unauthenticated peer with network access to a leafnode listener with compression enabled could crash the server during the pre-authentication leafnode handshake by sending repeated leafnode INFO protocol messages before authentication and account setup completed. This issue is fixed in versions 2.12.8 and 2.11.17.
- Record
AZL-92250- Updated
- 2026-11-05
OSVBIT-nats-2026-58250 No score
NATS Server: Pre-auth server crash via double INFO in leafnode handshake
NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.12.8 and 2.11.17, an unauthenticated peer with network access to a leafnode listener with compression enabled could crash the server during the pre-authentication leafnode handshake by sending repeated leafnode INFO protocol messages before authentication and account setup completed. This issue is fixed in versions 2.12.8 and 2.11.17.
- Record
BIT-nats-2026-58250- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
telegrafAzure Linux:3 |
before 1.31.0-27 | 1.31.0-27 |
natsBitnami |
before 2.11.17, 2.12.0 up to 2.12.8 | 2.11.172.12.8 |
nats-serverDebian:12 |
All versions, plus listed versions 2.10.1-12.10.16-12.10.18-12.10.24-12.10.27-1 Show 11 moreShow less2.10.3-12.10.4-12.10.7-12.12.4-12.12.6-12.14.1-12.14.3-12.14.6-12.15.1-12.9.10-12.9.19-1 |
None known |
nats-serverDebian:13 |
All versions, plus listed versions 2.10.27-12.12.4-12.12.6-12.14.1-12.14.3-12.14.6-12.15.1-1 |
None known |
nats-serverDebian:14 |
before 2.14.1-1, plus listed versions 2.10.27-12.12.4-12.12.6-1 |
2.14.1-1 |
nats_server_jllJulia |
before 2.14.3+0 | 2.14.3+0 |
nats-serverUbuntu:24.04:LTS |
All versions, plus listed versions 2.9.19-1build12.10.3-12.10.4-12.10.7-12.10.7-1ubuntu0.12.10.7-1ubuntu0.22.10.7-1ubuntu0.3 |
None known |
nats-serverUbuntu:25.10 |
All versions, plus listed versions 2.10.24-12.10.27-1 |
None known |
nats-serverUbuntu:Pro:26.04:LTS |
All versions, plus listed versions 2.10.27-12.10.27-1build12.10.27-1ubuntu0.26.04.1~esm1 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| facts | OSV | |
| first indexed | CVE List, EUVD, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-58250 is a high vulnerability (CVSS 7.5) in Linuxfoundation Nats-server, published July 8, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.74%, the 54th percentile. Fixed in telegraf 1.31.0-27.
References
github.com/nats-io/nats-server/security/advisories/GHSA-3g5q-cfh2-cq67
nvd.nist.gov/vuln/detail/CVE-2026-58250