Cyber Resilience

CVE-2026-33006

Apache Http Server ≤ 2.4.67

Published
04 May 2026
Modified
17 June 2026
Patch / advisory
CVSS Score v3.1 4.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
EPSS Score 0.0056 44th percentile
Risk Priority 40 floored blend · peak EPSS

Summary

CVE-2026-33006 is a medium-severity Observable Timing Discrepancy (CWE-208) vulnerability in Apache Http Server. Its CVSS base score is 4.8 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Password Guessing (T1110.001); ranked at the 44th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SA-8 (Security and Privacy Engineering Principles) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

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.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1110.001 Password Guessing Credential Access
Adversaries with no prior knowledge of legitimate credentials within the system or environment may guess passwords to attempt access to accounts.
T1087 Account Discovery Discovery
Adversaries may attempt to get a listing of valid accounts, usernames, or email addresses on a system or within a compromised environment.
T1087.001 Local Account Discovery
Adversaries may attempt to get a listing of local system accounts.
T1087.002 Domain Account Discovery
Adversaries may attempt to get a listing of domain accounts.
T1087.003 Email Account Discovery
Adversaries may attempt to get a listing of email addresses and accounts.
T1087.004 Cloud Account Discovery
Adversaries may attempt to get a listing of cloud accounts.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-23918Same product: Apache Http Server
CVE-2026-43951Same product: Apache Http Server
CVE-2025-49506Same vendor: Apache
CVE-2026-34032Same product: Apache Http Server
CVE-2025-65082Same product: Apache Http Server
CVE-2026-48913Same product: Apache Http Server
CVE-2025-49812Same product: Apache Http Server
CVE-2025-54090Same product: Apache Http Server
CVE-2026-28780Same product: Apache Http Server
CVE-2023-25690Same product: Apache Http Server

Affected Assets

apache
http server
≤ 2.4.67

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V11.2.4

Mitigating Controls (NIST 800-53 r5) AI

Developer testing can include timing analysis or side-channel test cases that reveal observable timing discrepancies.

Engineering principles can mandate constant-time algorithms and side-channel resistance so timing discrepancies are never introduced.

Requiring approved cryptographic modules and algorithms implicitly demands implementations free of observable timing leaks.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly require constant-time implementations that eliminate observable timing discrepancies.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

none

Consistent reference clocks limit the attacker's ability to measure or manipulate timing differences that could reveal internal state or processing paths.

References