CVE-2023-50247

h2o QUIC state exhaustion DoS

Description

h2o is an HTTP server with support for HTTP/1.x, HTTP/2 and HTTP/3. The QUIC stack (quicly), as used by H2O up to commit 43f86e5 (in version 2.3.0-beta and prior), is susceptible to a state exhaustion attack. When H2O is serving HTTP/3, a remote attacker can exploit this vulnerability to progressively increase the memory retained by the QUIC stack. This can eventually cause H2O to abort due to memory exhaustion. The vulnerability has been resolved in commit d67e81d03be12a9d53dc8271af6530f40164cd35. HTTP/1 and HTTP/2 are not affected by this vulnerability as they do not use QUIC. Administrators looking to mitigate this issue without upgrading can disable HTTP/3 support.

Category

3.7
CVSS
Severity: Low
CVSS 3.1 •
EPSS 0.56%
Vendor Advisory github.com
Affected: h2o h2o
Published at:
Updated at:

References

Link Tags
https://github.com/h2o/h2o/security/advisories/GHSA-2ch5-p59c-7mv6 patch vendor advisory
https://github.com/h2o/h2o/commit/d67e81d03be12a9d53dc8271af6530f40164cd35 patch

Frequently Asked Questions

What is the severity of CVE-2023-50247?
CVE-2023-50247 has been scored as a low severity vulnerability.
How to fix CVE-2023-50247?
To fix CVE-2023-50247, 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-2023-50247 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-50247 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-50247?
CVE-2023-50247 affects h2o h2o.
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