Description
Deno is a JavaScript, TypeScript, and WebAssembly runtime. Prior to 2.7.5, a Deno program that opens a client WebSocket connection could be crashed by the remote server. While handling the WebSocket handshake response, Deno parsed the Sec-WebSocket-Protocol and Sec-WebSocket-Extensions response headers in a way that assumed their bytes were always printable ASCII. A response header containing non-visible-ASCII bytes (0x80-0xFF) caused a panic that aborted the entire Deno process. This vulnerability is fixed in 2.7.5.
Severity (CVSS)
| Base score | 4.3 |
|---|---|
| Severity | Medium |
| Version | CVSS 3.1 |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L |
| Provided by | CNA |
Weaknesses
- CWE-248 — CWE-248: Uncaught Exception
Affected products
| Vendor | Product | Versions |
|---|---|---|
| denoland | deno | < 2.7.5 |
References
- https://github.com/denoland/deno/security/advisories/GHSA-x2qc-cmh9-f4hf (x_refsource_CONFIRM)
Generated from the official CVE List on 24 Jun 2026 09:35 UTC.