CVE-2025-53020

Publication date 10 July 2025

Last updated 26 August 2025

Ubuntu priority

Cvss 3 Severity Score

Late Release of Memory after Effective Lifetime vulnerability in Apache HTTP Server. This issue affects Apache HTTP Server: from 2.4.17 up to 2.4.63. Users are recommended to upgrade to version 2.4.64, which fixes the issue.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
apache2	25.04 plucky	Fixed 2.4.63-1ubuntu1.1
	24.04 LTS noble	Fixed 2.4.58-1ubuntu8.7
	22.04 LTS jammy	Fixed 2.4.52-1ubuntu4.15
	20.04 LTS focal	Fixed 2.4.41-4ubuntu3.23+esm2
	18.04 LTS bionic	Fixed 2.4.29-1ubuntu4.27+esm6
	16.04 LTS xenial	Fixed 2.4.18-2ubuntu3.17+esm16
	14.04 LTS trusty	Not affected

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Notes

mdeslaur

Described as "HTTP/2 DoS by Memory Increase"

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
apache2	Upstream: ef98f4f

Severity score breakdown

Parameter	Value
Base score	7.5 · High
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	None
Integrity impact	None
Availability impact	High
Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H