CVE-2026-49975

Publication date 3 June 2026

Last updated 18 June 2026

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

7.5 · High

Score breakdown

Description

Memory Allocation with Excessive Size Value vulnerability in Apache HTTP Server's mod_http leads to denial of service via malicious HTTP requests. This issue affects Apache HTTP Server: from 2.4.17 through 2.4.67.

Read the notes from the security team

Status

Package Ubuntu Release Status
apache2 26.04 LTS resolute
Fixed 2.4.66-2ubuntu2.2
25.10 questing
Fixed 2.4.64-1ubuntu3.5
24.04 LTS noble
Fixed 2.4.58-1ubuntu8.13
22.04 LTS jammy
Fixed 2.4.52-1ubuntu4.21
20.04 LTS focal
Vulnerable
18.04 LTS bionic
Vulnerable
16.04 LTS xenial
Vulnerable
14.04 LTS trusty
Not affected
nginx 26.04 LTS resolute
Fixed 1.28.3-2ubuntu1.5
25.10 questing
Fixed 1.28.0-6ubuntu1.7
24.04 LTS noble
Fixed 1.24.0-2ubuntu7.12
22.04 LTS jammy
Fixed 1.18.0-6ubuntu14.15
20.04 LTS focal
Vulnerable
18.04 LTS bionic
Vulnerable
16.04 LTS xenial
Not affected
14.04 LTS trusty
Not affected

Notes

mdeslaur

nginx fixed this by releasing 1.29.8 with a max_headers directive with a default of 1000. They did not mention this release on their security page, and did not assign an nginx specific CVE to this issue. The nginx fix for this issue breaks ABI and introduced a regression causing nginx to crash when being used with external modules. The CVE fix was reverted in 8398-2. USN-8398-3 provided a complete fix for this issue.

Patch details

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

Package Patch details
apache2
nginx

Severity score breakdown

CVSS version: CVSS v3.0

Base score 7.5 · High

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

Related Ubuntu Security Notices (USN)

Other references

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