Medium severity · published Jul 8, 2026
CVE-2026-58207
NATS Server: Remote crash via integer overflow in Connz pagination
6.5
CVSS
0.6%
EPSS
No
On KEV
Description
NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.3 and 2.12.12, a client able to send account-scoped connection monitoring requests could crash the server by supplying Connz pagination Offset and Limit values that overflowed internal arithmetic before the response window was safely bounded. This issue is fixed in versions 2.14.3 and 2.12.12.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 46% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
NA
nats-server · nats-io
< 2.12.12; >= 2.14.0-RC.1, < 2.14.3 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-58207
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-58207
Patch
https://github.com/nats-io/nats-server/commit/2ae047139e37a38cb01e259a67909e7a39fa38e9
Patch
https://github.com/nats-io/nats-server/commit/894d9411927681d66ce349bf1afe49608dc0c1a3
Release Notes
https://github.com/nats-io/nats-server/releases/tag/v2.12.12
Release Notes
https://github.com/nats-io/nats-server/releases/tag/v2.14.3
Mitigation
https://github.com/nats-io/nats-server/security/advisories/GHSA-q59r-vq66-pxc2
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