CVE-2026-33006: Apache HTTP Server: mod_auth_digest timing attack

Published May 4, 2026
·
Updated

A timing attack against modauthdigest in Apache HTTP Server 2.4.66 allows a bypass of Digest authentication by a remote attacker.

Other sources

Apache HTTP Server: modauthdigest timing attack

Microsoft

Affected Software

4 affected componentsFixes available
Apache HTTP Server=2.4.66
Apache HTTP Server<2.4.67
debian/apache2<=2.4.62-1~deb11u1
2.4.67-1~deb11u32.4.68-1~deb12u12.4.67-1~deb12u32.4.68-1~deb13u12.4.67-1~deb13u32.4.68-1
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 debian/apache2 to a version that resolves this vulnerability.

    Fixed in 2.4.67-1~deb11u3Fixed in 2.4.68-1~deb12u1Fixed in 2.4.67-1~deb12u3Fixed in 2.4.68-1~deb13u1Fixed in 2.4.67-1~deb13u3Fixed in 2.4.68-1
  2. Upgrade

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

    Fixed in 2.4.67-1
  3. Upgrade

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

    Fixed in 2.4.67Patch CVE-2026-33006

Event History

May 4, 2026
CVE Published
via MITRE·02:42 PM
Data Sourced
via MITRE·02:42 PM
DescriptionWeakness
Data Sourced
via Red Hat·03:01 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·03:16 PM
DescriptionSeverityWeaknessAffected Software
May 7, 2026
Data Sourced
via Microsoft·08:11 AM
DescriptionSeverityWeaknessAffected Software
Updated
via Microsoft·08:11 AM
DescriptionSeverity
Jul 22, 2026
Data Sourced
via Ubuntu·08:18 PM
RemedyDescriptionSeverityAffected Software
Data Sourced
via Debian·08:20 PM
DescriptionAffected Software
Data Sourced
via Launchpad·08:20 PM
Description

Frequently Asked Questions

1

What is the severity of CVE-2026-33006?

CVE-2026-33006 is rated as a high-severity vulnerability due to its potential for unauthorized authentication bypass.

2

How do I fix CVE-2026-33006?

To fix CVE-2026-33006, upgrade Apache HTTP Server from version 2.4.66 to version 2.4.67.

3

What vulnerability does CVE-2026-33006 address?

CVE-2026-33006 addresses a timing attack vulnerability in mod_auth_digest that allows remote attackers to bypass Digest authentication.

4

Which versions of Apache HTTP Server are affected by CVE-2026-33006?

Apache HTTP Server version 2.4.66 is the only version affected by CVE-2026-33006.

5

Can CVE-2026-33006 be exploited remotely?

Yes, CVE-2026-33006 can be exploited remotely, allowing attackers to bypass authentication through a timing attack.

Contact

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