RHSA-2026:57844: Moderate: mod_md security update
Moderate: modmd security update
Other sources
This module manages common properties of domains for one or more virtual hosts. Specifically it can use the ACME protocol to automate certificate provisioning. Certificates will be configured for managed domains and their virtual hosts automatically, including at renewal.Security Fix(es): httpd: modmd: unrestricted OCSP response leads to resource exhaustion (CVE-2026-29168) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
— Red Hat
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
httpd: mod_mdto a version that resolves this vulnerability.Patch CVE-2026-29168
Event History
Frequently Asked Questions
Which deployments are most likely to be exposed?
Deployments using Apache httpd's mod_md to manage domains and automate certificate provisioning through ACME are the relevant exposure scope. The advisory applies to the listed Red Hat Enterprise Linux offerings.
What is the impact of exploitation?
An unrestricted OCSP response in mod_md can lead to resource exhaustion. The advisory classifies the update as Moderate severity.
How can I determine whether this issue is relevant to my servers?
Check whether Apache httpd has mod_md enabled and is configured to manage domains or automatically provision and renew certificates using ACME. Systems not using mod_md for these functions are not identified by the advisory as affected.