CVE-2023-26103

Name of the Vulnerable Software and Affected Versions deno versions prior to 1.31.0

Description The issue is related to Regular Expression Denial of Service (ReDoS) due to the upgradeWebSocket function, which contains regexes in the form of /s*,s*/, used for splitting the Connection/Upgrade header. A specially crafted Connection/Upgrade header can be used to significantly slow down a web socket server.

Recommendations For deno versions prior to 1.31.0, it is recommended that users upgrade to Deno 1.31.0. As a temporary workaround, consider restricting access to the upgradeWebSocket function until a patch is available. Avoid using the Connection/Upgrade header with specially crafted values in the affected API endpoint until the issue is resolved.