Cyber Resilience

CVE-2026-29169

Memory Safety in Apache Http Server ≤ 2.4.67

Published
04 May 2026
Modified
17 June 2026
Patch / advisory
CVSS Score v3.1 7.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0059 45th percentile
Risk Priority 58 floored blend · peak EPSS

Summary

CVE-2026-29169 is a high-severity NULL Pointer Dereference (CWE-476) vulnerability in Apache Http Server. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Endpoint Denial of Service (T1499); ranked at the 45th 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-15 (Development Process, Standards, and Tools) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2026-29169 is a NULL pointer dereference vulnerability in the mod_dav_lock module of Apache HTTP Server versions 2.4.66 and earlier. This flaw occurs when processing a malicious request, potentially leading to a server crash. The mod_dav_lock module is not used internally by mod_dav or mod_dav_fs, with its only known use case being mod_dav_svn from Apache Subversion versions earlier than 1.2.0. The vulnerability is classified under CWE-476 and carries a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).

A remote, unauthenticated attacker can exploit this vulnerability over the network with low complexity and no user interaction by sending a specially crafted request to a server with mod_dav_lock enabled. Successful exploitation results in a denial-of-service condition through server crashes, disrupting availability without impacting confidentiality or integrity.

The official Apache HTTP Server security advisory recommends upgrading to version 2.4.66, which addresses the issue, or removing the mod_dav_lock module entirely. Additional details are available in the Apache vulnerabilities page at https://httpd.apache.org/security/vulnerabilities_24.html and the oss-security mailing list announcement at http://www.openwall.com/lists/oss-security/2026/05/04/20.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

A NULL pointer dereference in mod_dav_lock in Apache HTTP Server 2.4.66 and earlier may allow an attacker to crash the server with a malicious request.mod_dav_lock is not used internally by mod_dav or mod_dav_fs. The only known use-case for mod_dav_lock was…

more

mod_dav_svn from Apache Subversion earlier than version 1.2.0. Users are recommended to upgrade to version 2.4.66, which fixes this issue, or remove mod_dav_lock.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1499 Endpoint Denial of Service Impact
Adversaries may perform Endpoint Denial of Service (DoS) attacks to degrade or block the availability of services to users.
T1499.004 Application or System Exploitation Impact
Adversaries may exploit software vulnerabilities that can cause an application or system to crash and deny availability to users.
T1489 Service Stop Impact
Adversaries may stop or disable services on a system to render those services unavailable to legitimate users.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-33007Same product: Apache Http Server
CVE-2025-49630Same product: Apache Http Server
CVE-2026-44186Same product: Apache Http Server
CVE-2024-38477Same product: Apache Http Server
CVE-2025-53020Same product: Apache Http Server
CVE-2024-36387Same product: Apache Http Server
CVE-2026-23918Same product: Apache Http Server
CVE-2023-43622Same product: Apache Http Server
CVE-2026-29168Same product: Apache Http Server
CVE-2026-43951Same product: Apache Http Server

Affected Assets

apache
http server
≤ 2.4.67

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and evaluation (including static analysis) directly finds null-dereference bugs before deployment.

Documented development standards and tools can enforce null-safety rules and safe pointer usage.

Engineering principles can mandate defensive coding such as explicit null checks before dereference.

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 (static analysis, code review, safe coding standards) directly prevent NULL dereference bugs during development.

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.

finds

Security testing can detect NULL dereference defects before release.

prevents

Secure SDLC mandates defensive coding practices that can prevent NULL dereferences.

prevents

Application security requirements can specify input validation and pointer-safety rules.

prevents

Secure architecture principles encourage defensive design that avoids unsafe pointer use.

prevents

Secure coding standards directly require NULL-pointer checks and safe dereference patterns.

References