A flaw in Node.js TLS error handling allows remote attackers to crash or exhaust resources of a TLS server when pskCallback or ALPNCallback are in use. Synchronous exceptions thrown during these callbacks bypass standard TLS error handling paths (tlsClientError and error), causing either immediate process termination or silent file descriptor leaks that eventually lead to denial of service. Because these callbacks process attacker-controlled input during the TLS handshake, a remote client can repeatedly trigger the issue. This vulnerability affects TLS servers using PSK or ALPN callbacks across Node.js versions where these callbacks throw without being safely wrapped.
Weakness
The product does not properly control the allocation and maintenance of a limited resource.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Node.js | Nodejs | 4.0.0 (including) | 20.20.0 (excluding) |
| Node.js | Nodejs | 22.0.0 (including) | 22.22.0 (excluding) |
| Node.js | Nodejs | 24.0.0 (including) | 24.13.0 (excluding) |
| Node.js | Nodejs | 25.0.0 (including) | 25.3.0 (excluding) |
| Red Hat Enterprise Linux 10 | RedHat | nodejs24-1:24.13.0-1.el10_1 | * |
| Red Hat Enterprise Linux 10 | RedHat | nodejs22-1:22.22.0-3.el10_1 | * |
| Red Hat Enterprise Linux 8 | RedHat | nodejs:24-8100020260116121421.6d880403 | * |
| Red Hat Enterprise Linux 8 | RedHat | nodejs:22-8100020260119091831.6d880403 | * |
| Red Hat Enterprise Linux 8 | RedHat | nodejs:20-8100020260119100525.489197e6 | * |
| Red Hat Enterprise Linux 9 | RedHat | nodejs:24-9070020260117213814.rhel9 | * |
| Red Hat Enterprise Linux 9 | RedHat | nodejs:22-9070020260117213838.rhel9 | * |
| Red Hat Enterprise Linux 9 | RedHat | nodejs:20-9070020260117213748.rhel9 | * |
| Nodejs | Ubuntu | plucky | * |
| Nodejs | Ubuntu | upstream | * |
Potential Mitigations
Mitigation of resource exhaustion attacks requires that the target system either:
The first of these solutions is an issue in itself though, since it may allow attackers to prevent the use of the system by a particular valid user. If the attacker impersonates the valid user, they may be able to prevent the user from accessing the server in question.
The second solution is simply difficult to effectively institute – and even when properly done, it does not provide a full solution. It simply makes the attack require more resources on the part of the attacker.
Related Attack Patterns
- https://cwe.mitre.org/data/definitions/147.html
- https://cwe.mitre.org/data/definitions/227.html
- https://cwe.mitre.org/data/definitions/492.html