nezhahq nezha up to 2.1.x Dashboard /api/v1/terminal createTerminal allocation of resources

Summaryinfo

A vulnerability, which was classified as problematic, was found in nezhahq nezha up to 2.1.x. This impacts the function createTerminal of the file /api/v1/terminal of the component Dashboard. The manipulation results in allocation of resources. This vulnerability is cataloged as CVE-2026-53522. The attack may be launched remotely. There is no exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic has been found in nezhahq nezha up to 2.1.x. Affected is the function createTerminal of the file /api/v1/terminal of the component Dashboard. The manipulation with an unknown input leads to a allocation of resources vulnerability. CWE is classifying the issue as CWE-770. The product allocates a reusable resource or group of resources on behalf of an actor without imposing any restrictions on the size or number of resources that can be allocated, in violation of the intended security policy for that actor. This is going to have an impact on availability. CVE summarizes:

Nezha Monitoring is a self-hostable, lightweight, servers and websites monitoring and O&M tool. From version 1.0.0 to before version 2.2.0, the Nezha dashboard exposes two endpoints that create long-lived WebSocket streams to monitored agents: POST /api/v1/terminal → createTerminal() (terminal.go:27-67) and POST /api/v1/file → createFM() (fm.go:28-67). Both call rpc.NezhaHandlerSingleton.CreateStream(streamId, ...) which inserts a new ioStreamContext into an unbounded map[string]*ioStreamContext (s.ioStreams in io_stream.go:59-67). There is no per-user rate limit, no global semaphore, and no per-server connection cap. This issue has been patched in version 2.2.0.

The advisory is shared for download at github.com. This vulnerability is traded as CVE-2026-53522 since 06/09/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1499.

Upgrading to version 2.2.0 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

• nezhahq

Name

• nezha

Version

• 2.0
• 2.1

Website

• Product: https://github.com/nezhahq/nezha/

CPE 2.3info

• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Once again VulDB remains the best source for vulnerability data.

Discussion