CVE-2026-29169

Description

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 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.

Overview

State: PUBLISHED
Assigner (CNA): apache
CVSS severity: high
CVSS score: 7.5 / 10
CVSS vector: AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Effective score: 7.5 / 10 HIGH source: CNA overview
MSRC score: 7.5 / 10 HIGH MS rating: Important
CWE(s): CWE-476
Reserved: 2026-03-04
Published: 2026-05-04 16:48 UTC
Last updated: 2026-05-05 22:23 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/29xxx/CVE-2026-29169.json
Linked Threat: CVE-2026-29169 — CVE-2026-29169

NVD triage scoring NVD CVE 2.0

Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.

NVD published: 2026-05-04 15:16:03 UTC
NVD last modified: 2026-05-05 21:16:21 UTC
NVD CVSS v3.1: 7.5 / 10 HIGH source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
NVD CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Exploitability subscore: 3.9 / 10
Impact subscore: 3.6 / 10
EPSS score: 0.0058 (probability of exploitation in next 30 days)
EPSS percentile: 69.04% vs all CVEs — higher = more likely to be exploited, as of 2026-05-25

European Union Vulnerability Database ENISA EUVD

ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.

EUVD ID: EUVD-2026-26957
Assigner: apache
Published: May 4, 2026, 2:48:29 PM
Updated: May 5, 2026, 8:23:49 PM
EUVD base score (CVSS 3.1): 7.5 / 10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EUVD-reported EPSS: 0.5800
Vendors: Apache Software Foundation
Products: Apache HTTP Server (0 ≤2.4.66)

ENISA description: 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 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.

EUVD references (1)

https://httpd.apache.org/security/vulnerabilities_24.html

Microsoft Security Response Center MSRC

Microsoft's vendor-authoritative record from the Security Update Guide — its own CVSS score, impact, severity rating, exploit assessment, and KB-article fixes. Refreshed 2026-08-12 01:09 UTC (source: CVRF).

MS severity: Important
MS CVSS base score: 7.5 / 10 (temporal 7.5)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Release: 2026-May

Microsoft remediations / KB articles (2)

CBL-Mariner Releases — Vendor Fix / Security Update (fixed build 2.4.67-1)
https://learn.microsoft.com/en-us/azure/azure-linux/tutorial-azure-linux-upgrade — None Available / CBL-Mariner Releases

Affected products (1)

Vendor	Product	Versions	Platforms
Apache Software Foundation	Apache HTTP Server	`0` (affected)	—

Affected products — CPE 2.3 (1) NVD

NVD's normalized CPE 2.3 matchers, used by vendor tools (vulnerability scanners, asset managers) for automated detection. Compare with the CNA's free-text "Affected products" section above.

cpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:*

Vendor references (1)

References embedded in the original CVE record by the assigning CNA.

https://httpd.apache.org/security/vulnerabilities_24.html vendor-advisory

MITRE references (1) cveawg.mitre.org

Pulled from MITRE's CVE Services API by the 🛰 Backfill from MITRE button.

https://httpd.apache.org/security/vulnerabilities_24.html vendor-advisory

Web references (12)

DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.

MSRC update guide: CVE-2026-29169 msrc
None Available msrc
https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-26957 rapid7:euvd.enisa.europa.eu
http://cwe.mitre.org/data/definitions/476.html rapid7:cwe.mitre.org
https://attackerkb.com/topics/CVE-2026-29169 rapid7:attackerkb.com
https://security.alpinelinux.org/vuln/CVE-2026-29169 rapid7:security.alpinelinux.org
http://www.openwall.com/lists/oss-security/2026/05/05/12 tenable:www.openwall.com
http://www.openwall.com/lists/oss-security/2026/05/04/20 tenable:www.openwall.com
https://nvd.nist.gov/vuln/detail/CVE-2026-29169 tenable:nvd.nist.gov
https://www.securityweek.com/critical-high-severity-vulnerabilities-patched-in-apache-mina-http-server/ tenable:www.securityweek.com
https://www.cve.org/CVERecord?id=CVE-2026-29169 tenable:www.cve.org
https://www.first.org/epss/ tenable:www.first.org

NVD-tagged references (3)

Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.

http://www.openwall.com/lists/oss-security/2026/05/04/20 af854a3a-2127-422b-91ae-364da2661108 Mailing ListThird Party Advisory
https://httpd.apache.org/security/vulnerabilities_24.html security@apache.org Vendor Advisory
http://www.openwall.com/lists/oss-security/2026/05/05/12 af854a3a-2127-422b-91ae-364da2661108

Remediations (18)

Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.

cve-details - Red Hat Customer Portal

web:access.redhat.com

Learn about our open source products, services, and company. You are here

2026-05-23 21:15 UTC
Microsoft Patch Tuesday April 2026 - 168 Vulnerabilities Fixed ...

web:cybersecuritynews.com

Microsoft has released its April 2026 Patch Tuesday security update, addressing 168 vulnerabilities across its product portfolio including one actively exploited zero-day and one publicly disclosed flaw that organizations must prioritize immediately.

2026-05-23 21:15 UTC
Nvd - Cve-2026-29169

web:nvd.nist.gov

An official website of the United States government Here's how you know

2026-05-23 21:15 UTC
Security Update Guide - Microsoft

web:portal.msrc.microsoft.com

The Security Update Guide provides information on the latest Microsoft security updates, helping users understand and address potential vulnerabilities effectively.

2026-05-23 21:15 UTC
CVE-2026-29169 - security-tracker.debian.org

web:security-tracker.debian.org

Vulnerable and fixed packages The table below lists information on source packages.

2026-05-23 21:15 UTC
CVE-2026-29169 | Ubuntu

web:ubuntu.com

Ubuntu is an open source software operating system that runs from the desktop, to the cloud, to all your internet connected things.

2026-05-23 21:15 UTC
CVE-2026-29169: Apache HTTP Server mod_dav_lock Indirect Lock Crash ...

web:vulert.com

Learn about CVE-2026-29169 , a vulnerability in Apache HTTP Server's mod_dav_lock module that can cause server crashes. Find out how to fix it and check your application with Vulert.

2026-05-23 21:15 UTC
Critical Patches Issued for Microsoft Products, May 12, 2026

web:www.cisecurity.org

<p>Multiple vulnerabilities have been discovered in Microsoft products, the most severe of which could allow for remote code execution. Successful exploitation of the most severe of these vulnerabilities could result in an attacker gaining the same privileges as the logged-on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or ...

2026-05-23 21:15 UTC
Emergency patch issued for Microsoft Office, 365 over hacking threat - MSN

web:www.msn.com

Microsoft suggests the threat is being used in phishing attacks against vulnerable systems since successful exploitation requires local access to the PC.

2026-05-23 21:15 UTC
Oracle Critical Patch Update Advisory - April 2026

web:www.oracle.com

This Critical Patch Update contains 481 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at April 2026 Critical Patch Update: Executive Summary and Analysis.

2026-05-23 21:15 UTC
Microsoft Patch Tuesday March 2026 - 78 Vulnerabilities Fixed ...

web:cybersecuritynews.com

Microsoft released its March 2026 Patch Tuesday security update on March 10, 2026 , addressing 78 vulnerabilities across Windows, Microsoft Office, Azure, SQL Server, and .NET. The update includes one actively exploited zero-day vulnerability and multiple Critical-rated flaws demanding immediate attention from security teams. The most urgent fix this month is CVE - 2026 -21262, the sole zero-day ...

2026-05-26 02:45 UTC
Nvd - Cve-2026-8969

web:nvd.nist.gov

An official website of the United States government Here's how you know

2026-05-26 02:45 UTC
Addressing Exchange Server May 2026 vulnerability CVE-2026-42897

web:techcommunity.microsoft.com

We wanted to tell you how to address the Exchange Server May 2026 vulnerability CVE - 2026 -42897.

2026-05-26 02:45 UTC
April 2026 Patch Tuesday: Updates and Analysis | CrowdStrike

web:www.crowdstrike.com

Microsoft's April 2026 Patch Tuesday addresses 164 CVEs , featuring 8 Critical vulnerabilities, one exploited zero-day, and one disclosed zero-day.

2026-05-26 02:45 UTC
Microsoft Confirms Active 0-Day Exploit—Check Emergency Mitigation

web:www.forbes.com

Updated May 17: This article, originally published May 16, has been updated to include further details on the emergency mitigation process recommended after the CVE - 2026 -42897 Microsoft Exchange ...

2026-05-26 02:45 UTC
Microsoft May 2026 Patch Tuesday Fixes 130+ Vulnerabilities ... - LinkedIn

web:www.linkedin.com

Microsoft has released its May 2026 Patch Tuesday security updates, addressing more than 130 vulnerabilities across its software ecosystem, including Windows, Microsoft Office, SharePoint Server ...

2026-05-26 02:45 UTC
CVE-2026-29169 - High Vulnerability - TheHackerWire

web:www.thehackerwire.com

CVE-2026-29169 is a High severity vulnerability (CVSS 7.5). A NULL pointer dereference in mod_dav_lock in Apache HTTP Server 2.4.66 and earlier may allow an attacker to crash the...

2026-05-26 02:45 UTC
Patch Tuesday May 2026: Security Updates & CVE Analysis

web:zecurit.com

Get the complete breakdown of Microsoft's May 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .

2026-05-26 02:45 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-29169.json.

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