Coder up to 2.38.3 Web Push subscription webpushSend user resource consumption

Summaryinfo

A vulnerability was found in Coder up to 2.29.23/2.34.15/2.36.10/2.37.7/2.38.3 and classified as problematic. Impacted is the function webpushSend of the file /api/v2/users/{user}/webpush/subscription of the component Web Push. Executing a manipulation of the argument User can lead to resource consumption. The identification of this vulnerability is CVE-2026-126405. The attack may be launched remotely. There is no exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Coder up to 2.29.23/2.34.15/2.36.10/2.37.7/2.38.3. It has been declared as problematic. This vulnerability affects the function webpushSend of the file /api/v2/users/{user}/webpush/subscription of the component Web Push. The manipulation of the argument user with an unknown input leads to a resource consumption vulnerability. The CWE definition for the vulnerability is CWE-400. The product does not properly control the allocation and maintenance of a limited resource. As an impact it is known to affect availability. CVE summarizes:

Coder 2.21.0 before 2.29.24, 2.30.0 before 2.34.16, 2.35.0 before 2.36.11, 2.37.0 before 2.37.8, and 2.38.0 before 2.38.4 reads Web Push endpoint responses in webpushSend with io.ReadAll, without a size limit or client timeout. Any authenticated user can register a subscription via POST /api/v2/users/{user}/webpush/subscription pointing to a server returning an endless body, exhausting coderd memory and crashing the API, dashboard, and workspace connections.

The advisory is shared for download at github.com. This vulnerability was named CVE-2026-126405 since 11/10/2026. The exploitation appears to be easy. The attack can be initiated 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 2.29.24, 2.34.16, 2.36.11, 2.37.8 or 2.38.4 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Name

• Coder

Version

• 2.29.0
• 2.29.1
• 2.29.2
• 2.29.3
• 2.29.4
• 2.29.5
• 2.29.6
• 2.29.7
• 2.29.8
• 2.29.9
• 2.29.10
• 2.29.11
• 2.29.12
• 2.29.13
• 2.29.14
• 2.29.15
• 2.29.16
• 2.29.17
• 2.29.18
• 2.29.19
• 2.29.20
• 2.29.21
• 2.29.22
• 2.29.23
• 2.34.0
• 2.34.1
• 2.34.2
• 2.34.3
• 2.34.4
• 2.34.5
• 2.34.6
• 2.34.7
• 2.34.8
• 2.34.9
• 2.34.10
• 2.34.11
• 2.34.12
• 2.34.13
• 2.34.14
• 2.34.15
• 2.36.0
• 2.36.1
• 2.36.2
• 2.36.3
• 2.36.4
• 2.36.5
• 2.36.6
• 2.36.7
• 2.36.8
• 2.36.9
• 2.36.10
• 2.37.0
• 2.37.1
• 2.37.2
• 2.37.3
• 2.37.4
• 2.37.5
• 2.37.6
• 2.37.7
• 2.38.0
• 2.38.1
• 2.38.2
• 2.38.3

Website

• Product: https://github.com/coder/coder/

CPE 2.3info

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CPE 2.2info

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