CVE-2026-55517

Name
CVE-2026-55517
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.
NVD Severity
unknown
Other trackers
CVE, NVD, CERT, CVE Details, CIRCL, Arch Linux, Debian, Red Hat, Ubuntu, Gentoo, SUSE (Bugzilla), SUSE (CVE), Mageia
Mailing lists
oss-security, full-disclosure, bugtraq
Exploits
Exploit DB, Metasploit
Forges
GitHub (code, issues), Aports (code, issues)

References

Type URI
security-advisories@github.com https://github.com/denoland/deno/security/advisories/GHSA-x2qc-cmh9-f4hf

Match rules

CPE URI Source package Min version Max version
cpe:2.3:a:deno:deno:*:*:*:*:*:*:*:* deno >= None < 2.7.5

Vulnerable and fixed packages

Source package Branch Version Maintainer Status
deno edge-community 2.7.4-r2 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
deno edge-community 2.7.4-r1 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
deno edge-community 2.7.4-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
deno edge-community 2.3.1-r8 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
deno edge-community 2.3.1-r7 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
deno edge-community 2.3.1-r6 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
deno edge-community 2.3.1-r5 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
deno edge-community 2.3.1-r4 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
deno edge-community 2.3.1-r3 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
deno edge-community 2.3.1-r2 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
deno edge-community 2.3.1-r1 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
deno edge-community 2.3.1-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
deno edge-community 2.0.6-r2 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
deno edge-community 2.0.6-r0 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable
deno 3.24-community 2.7.4-r2 Jakub Jirutka <jakub@jirutka.cz> possibly vulnerable