Riskcovery

CVE-2023-43622

Apache HTTP Server: DoS in HTTP/2 with initial windows size 0

State
Published
Severity
Not scored
Published
Oct 23, 2023
Updated
Feb 13, 2025
Reserved
Sep 20, 2023

Read the record on cve.org

Description

An attacker, opening a HTTP/2 connection with an initial window size of 0, was able to block handling of that connection indefinitely in Apache HTTP Server. This could be used to exhaust worker resources in the server, similar to the well known "slow loris" attack pattern. This has been fixed in version 2.4.58, so that such connection are terminated properly after the configured connection timeout.

This issue affects Apache HTTP Server: from 2.4.55 through 2.4.57.

Users are recommended to upgrade to version 2.4.58, which fixes the issue.

Scores

The record has no CVSS score.

Weaknesses

  • CWE-400 Uncontrolled Resource Consumption

Affected Products

ProductVersions
Apache HTTP ServerApache Software Foundation
  • 2.4.55 through 2.4.57Affected

References

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