Apache HTTP Server up to 2.4.66 mod_auth_digest timing discrepancy

CVSS Meta Temp Score
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CTI Interest Score
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3.6$0-$5k0.00

Summaryinfo

A vulnerability was found in Apache HTTP Server up to 2.4.66. It has been classified as problematic. This affects an unknown part of the component mod_auth_digest. This manipulation causes timing discrepancy. This vulnerability is tracked as CVE-2026-33006. The attack is possible to be carried out remotely. No exploit exists. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability has been found in Apache HTTP Server up to 2.4.66 and classified as problematic. Affected by this vulnerability is an unknown code block of the component mod_auth_digest. The manipulation with an unknown input leads to a timing discrepancy vulnerability. The CWE definition for the vulnerability is CWE-208. Two separate operations in a product require different amounts of time to complete, in a way that is observable to an actor and reveals security-relevant information about the state of the product, such as whether a particular operation was successful or not. As an impact it is known to affect confidentiality. The summary by CVE is:

A timing attack against mod_auth_digest in Apache HTTP Server 2.4.66 allows a bypass of Digest authentication by a remote attacker. Users are recommended to upgrade to version 2.4.67, which fixes this issue.

The weakness was disclosed by Nitescu Lucian. It is possible to read the advisory at httpd.apache.org. This vulnerability is known as CVE-2026-33006 since 03/17/2026. The exploitation appears to be difficult. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 05/13/2026). The attack technique deployed by this issue is T1592 according to MITRE ATT&CK.

The vulnerability scanner Nessus provides a plugin with the ID 312249 (FreeBSD : www/apache24 -- Multiple vulnerabilities (1ccc383b-486a-11f1-8b62-8447094a420f)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 2.4.67 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (312249), EUVD (EUVD-2026-26961) and CERT Bund (WID-SEC-2026-1354). Be aware that VulDB is the high quality source for vulnerability data.

Affected

  • Debian Linux
  • Red Hat Enterprise Linux
  • Fedora Linux
  • Ubuntu Linux
  • IBM HTTP Server
  • Microsoft Azure Linux
  • Apache HTTP Server

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 3.7
VulDB Meta Temp Score: 3.6

VulDB Base Score: 3.7
VulDB Temp Score: 3.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Timing discrepancy
CWE: CWE-208 / CWE-203 / CWE-200
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 312249
Nessus Name: FreeBSD : www/apache24 -- Multiple vulnerabilities (1ccc383b-486a-11f1-8b62-8447094a420f)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: HTTP Server 2.4.67

Timelineinfo

03/17/2026 CVE reserved
05/04/2026 +47 days Advisory disclosed
05/04/2026 +0 days VulDB entry created
05/13/2026 +9 days VulDB entry last update

Sourcesinfo

Vendor: apache.org

Advisory: httpd.apache.org
Researcher: Nitescu Lucian
Status: Confirmed

CVE: CVE-2026-33006 (🔒)
GCVE (CVE): GCVE-0-2026-33006
GCVE (VulDB): GCVE-100-360967
EUVD: 🔒
CERT Bund: WID-SEC-2026-1354 - Apache HTTP Server: Mehrere Schwachstellen

Entryinfo

Created: 05/04/2026 17:19
Updated: 05/13/2026 12:13
Changes: 05/04/2026 17:19 (57), 05/04/2026 19:52 (1), 05/05/2026 12:16 (7), 05/06/2026 06:27 (2), 05/13/2026 12:13 (1)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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