CVEvulnerability

CVE-2026-55517

4.3 MEDIUM Published 2026-06-23 Modified 2026-10-25 Official page ↗
Status
Analyzed
Published
2026-06-23
Last modified
2026-10-25
Assigner
[email protected]
CVSS 3.1 ([email protected])
4.3 MEDIUM — CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
Weaknesses
CWE-248

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.

Affected configurations

• deno deno (< 2.7.5)

Related

Weakness · CWE (1)

  • CWE-248 Uncaught Exception weakness

References