CVE-2026-33857: Apache HTTP Server: Off-by-one OOB reads in AJP getter functions

Published May 4, 2026
·
Updated

Apache HTTP Server: Off-by-one OOB reads in AJP getter functions

Other sources

Out-of-bounds Read vulnerability in modproxyajp of

Apache HTTP Server.

This issue affects Apache HTTP Server: through 2.4.66.

Users are recommended to upgrade to version 2.4.67, which fixes the issue.

NVD

Affected Software

3 affected componentsFixes available
Apache HTTP Server<=2.4.66
Apache HTTP Server<2.4.67
Microsoft azl3 httpd 2.4.66-1<2.4.67-1
2.4.67-1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 2.4.67-1
  2. Upgrade

    Upgrade Apache HTTP Server to a version that resolves this vulnerability.

    Fixed in 2.4.67Patch CVE-2026-33857

Event History

May 4, 2026
CVE Published
via MITRE·01:07 PM
Data Sourced
via MITRE·01:07 PM
DescriptionWeakness
Data Sourced
via Red Hat·02:01 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·02:16 PM
DescriptionSeverityWeaknessAffected Software
May 7, 2026
Data Sourced
via Microsoft·08:12 AM
DescriptionSeverityWeaknessAffected Software
Updated
via Microsoft·08:12 AM
DescriptionSeverity

Frequently Asked Questions

1

What is the severity of CVE-2026-33857?

CVE-2026-33857 is classified as an Off-by-one Out-of-Bounds Read vulnerability in Apache HTTP Server.

2

How do I fix CVE-2026-33857?

To fix CVE-2026-33857, upgrade your Apache HTTP Server to version 2.4.67 or later.

3

Which versions of Apache HTTP Server are affected by CVE-2026-33857?

CVE-2026-33857 affects Apache HTTP Server versions up to and including 2.4.66.

4

What components of Apache HTTP Server are impacted by CVE-2026-33857?

The vulnerability CVE-2026-33857 specifically impacts the mod_proxy_ajp component of Apache HTTP Server.

5

Is there a workaround for CVE-2026-33857 if I cannot upgrade?

There are no known workarounds for CVE-2026-33857, so upgrading is the best mitigation.

Contact

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