CVE-2023-26103

Public Exploit

Description

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.

Category

5.3
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.09%
Third-Party Advisory snyk.io
Affected: n/a deno
Published at:
Updated at:

References

Link Tags
https://security.snyk.io/vuln/SNYK-RUST-DENO-3315970 third party advisory exploit technical description
https://github.com/denoland/deno/blob/2b247be517d789a37e532849e2e40b724af0918f/ext/http/01_http.js%23L395-L409 broken link
https://github.com/denoland/deno/pull/17722 patch
https://github.com/denoland/deno/commit/cf06a7c7e672880e1b38598fe445e2c50b4a9d06 patch
https://github.com/denoland/deno/releases/tag/v1.31.0 release notes

Frequently Asked Questions

What is the severity of CVE-2023-26103?
CVE-2023-26103 has been scored as a medium severity vulnerability.
How to fix CVE-2023-26103?
To fix CVE-2023-26103, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2023-26103 being actively exploited in the wild?
It is possible that CVE-2023-26103 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-26103?
CVE-2023-26103 affects n/a deno.
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