Vulnerability in Deno

CVE-2023-26103

Versions of the package deno before 1.31.0 are vulnerable 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.

Vulnerability class: ReDoS (Regular Expression Denial of Service)

EPSS: 0.012 (65.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.

Affected products

  • Deno
  • N/a Deno — versions 0

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2023-26103?
CVE-2023-26103 is a medium-severity vulnerability in Deno, classified under Inefficient Regular Expression Complexity. CVSS score: 5.3/10. Published 2023-02-25.
How severe is CVE-2023-26103?
Medium severity. CVSS v3 base score is 5.3 out of 10.
Is CVE-2023-26103 known to be exploited?
2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.