Apache2: A timing attack against mod_auth_digest in Apache HTTP Server 2.4.66 allows a bypass of Digest authentication by a remote attacker.
A timing attack vulnerability exists in mod_auth_digest of Apache HTTP Server version 2.4.66, allowing remote attackers to bypass Digest authentication. This issue is resolved in version 2.4.67. Multiple Ubuntu package versions of Apache 2.4.6 through 2.4.66 are affected. Users should upgrade to the fixed version to mitigate this vulnerability.
AI Analysis
Technical Summary
Apache HTTP Server 2.4.66 contains a timing attack vulnerability in the mod_auth_digest module that enables remote attackers to bypass Digest authentication. The vulnerability is fixed in version 2.4.67. The affected versions include a wide range of Ubuntu-specific Apache 2.4.x packages from 2.4.6 up to 2.4.66. The CVSS 3.1 vector indicates network attack vector, high attack complexity, no privileges required, no user interaction, unchanged scope, with low confidentiality and integrity impact and no availability impact.
Potential Impact
Successful exploitation allows a remote attacker to bypass Digest authentication, potentially granting unauthorized access to protected resources. The impact is limited to confidentiality and integrity with low severity, as indicated by the CVSS vector. There is no known exploitation in the wild at this time.
Mitigation Recommendations
Users are recommended to upgrade Apache HTTP Server to version 2.4.67 or later, which contains the official fix for this vulnerability. No other mitigations are specified. Patch status is confirmed by the vendor advisory recommending upgrade to 2.4.67.
Apache2: A timing attack against mod_auth_digest in Apache HTTP Server 2.4.66 allows a bypass of Digest authentication by a remote attacker.
Description
A timing attack vulnerability exists in mod_auth_digest of Apache HTTP Server version 2.4.66, allowing remote attackers to bypass Digest authentication. This issue is resolved in version 2.4.67. Multiple Ubuntu package versions of Apache 2.4.6 through 2.4.66 are affected. Users should upgrade to the fixed version to mitigate this vulnerability.
CVSS v3.1
Score 4.8medium
Affected software
pkg:deb/ubuntu/[email protected]+esm15?arch=source&distro=esm-infra-legacy/trustypkg:deb/ubuntu/[email protected]+esm20?arch=source&distro=esm-infra-legacy/xenialpkg:deb/ubuntu/[email protected]+esm11?arch=source&distro=esm-infra/bionicpkg:deb/ubuntu/[email protected]+esm6?arch=source&distro=esm-infra/focalpkg:deb/ubuntu/[email protected]?arch=source&distro=jammypkg:deb/ubuntu/[email protected]?arch=source&distro=noblepkg:deb/ubuntu/[email protected]?arch=source&distro=questingpkg:deb/ubuntu/[email protected]?arch=source&distro=resoluteRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Apache HTTP Server 2.4.66 contains a timing attack vulnerability in the mod_auth_digest module that enables remote attackers to bypass Digest authentication. The vulnerability is fixed in version 2.4.67. The affected versions include a wide range of Ubuntu-specific Apache 2.4.x packages from 2.4.6 up to 2.4.66. The CVSS 3.1 vector indicates network attack vector, high attack complexity, no privileges required, no user interaction, unchanged scope, with low confidentiality and integrity impact and no availability impact.
Potential Impact
Successful exploitation allows a remote attacker to bypass Digest authentication, potentially granting unauthorized access to protected resources. The impact is limited to confidentiality and integrity with low severity, as indicated by the CVSS vector. There is no known exploitation in the wild at this time.
Mitigation Recommendations
Users are recommended to upgrade Apache HTTP Server to version 2.4.67 or later, which contains the official fix for this vulnerability. No other mitigations are specified. Patch status is confirmed by the vendor advisory recommending upgrade to 2.4.67.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- UBUNTU-CVE-2026-33006
- Osv Schema Version
- 1.7.0
- Aliases
- []
- Ecosystems
- ["Ubuntu:Pro:14.04:LTS","Ubuntu:Pro:16.04:LTS","Ubuntu:Pro:18.04:LTS","Ubuntu:Pro:20.04:LTS","Ubuntu:22.04:LTS","Ubuntu:24.04:LTS","Ubuntu:25.10","Ubuntu:26.04:LTS"]
- Database Specific Severity
- null
- Cvss Version
- 3.1
Threat ID: 6a61511f9c2644c7f8da5f57
Added to database: 07/22/2026, 23:24:15 UTC
Last enriched: 07/23/2026, 06:53:16 UTC
Last updated: 07/31/2026, 19:22:58 UTC
Views: 18
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