Red Hat Fixes DNS and DHCP Flaws in dnsmasq on RHEL 8.8
Tech GuruQuick Answer
Check dnsmasq on RHEL 8.8 Update Services for SAP Solutions and Telecommunications Update Service. Apply RHSA-2026:96246 from the matching entitled repository. Validate configuration, restart dnsmasq in an approved window and test DNS resolution, DNSSEC and required DHCP leases.
Confirm Scope And Apply The Supported Remediation
What to do now: Record dnsmasq listeners, DNSSEC, DHCPv6, forwarding rules and the correct supported package channel. RHEL 8.8 Update Services for SAP Solutions and Telecommunications Update Service: installations of the dnsmasq packages requiring RHSA-2026:96246. Match the full installed RPM, architecture and repository to the vendor product tree; a universal upstream version range is not stated. Apply RHSA-2026:96246 through the entitled Red Hat repositories. The fixed source build is dnsmasq-0:2.79-26.el8_8.5. Install the matching binary packages for the supported stream and architecture. Validate configuration, restart dnsmasq in an approved window and test DNS resolution, DNSSEC and required DHCP leases.
Last verified: 2026-11-09 UTC. Recheck the authoritative advisory and supported distribution channel before changing production.
Scope And Authority
| Product scope | RHEL 8.8 Update Services for SAP Solutions and Telecommunications Update Service; dnsmasq |
|---|---|
| Advisory | RHSA-2026:96246 |
| CVEs | CVE-2026-2291, CVE-2026-4890, CVE-2026-4891, CVE-2026-4892, CVE-2026-4893 |
| Authoritative release date | November 9, 2026 at 12:39:15 UTC, from Red Hat CSAF initial_release_date. |
| Authority revision date | Red Hat records the substantive last-updated version at 2026-11-09T12:39:15+00:00. The CSAF generation timestamp is 2026-11-09T16:42:44+00:00; generation alone is not a material advisory revision. |
| Affected versions | RHEL 8.8 Update Services for SAP Solutions and Telecommunications Update Service: installations of the dnsmasq packages requiring RHSA-2026:96246. Match the full installed RPM, architecture and repository to the vendor product tree; a universal upstream version range is not stated. |
| Fixed version | dnsmasq-0:2.79-26.el8_8.5 |
| CVSS base score | 8.8 (highest authority-stated CVSS 3.1 base score) |
| CVSS severity | High (CVSS); Important (Red Hat impact) |
| Exploitation status | Red Hat does not state exploitation in this advisory.; no exploitation claim is inferred. |
Authority CVSS by Vulnerability
| CVE-2026-2291 | CVSS 3.1: 6.5 (Medium) |
|---|---|
| CVE-2026-4890 | CVSS 3.1: 7.5 (High) |
| CVE-2026-4891 | CVSS 3.1: 7.5 (High) |
| CVE-2026-4892 | CVSS 3.1: 8.8 (High) |
| CVE-2026-4893 | CVSS 3.1: 6.5 (Medium) |
What Changed
Red Hat released RHSA-2026:96246 for RHEL 8.8 Update Services for SAP Solutions and Telecommunications Update Service, addressing DNS cache and DNSSEC parsing flaws, a DHCPv6 buffer overflow and EDNS Client Subnet validation bypass. The update provides the distribution packages listed below; keep the Red Hat release and support channel matched during remediation.
What To Validate Now
- Inventory. Record dnsmasq listeners, DNSSEC, DHCPv6, forwarding rules and the correct supported package channel.
- Establish applicability. RHEL 8.8 Update Services for SAP Solutions and Telecommunications Update Service: installations of the dnsmasq packages requiring RHSA-2026:96246. Match the full installed RPM, architecture and repository to the vendor product tree; a universal upstream version range is not stated.
- Remediate. Apply RHSA-2026:96246 through the entitled Red Hat repositories. The fixed source build is dnsmasq-0:2.79-26.el8_8.5. Install the matching binary packages for the supported stream and architecture.
- Validate. Validate configuration, restart dnsmasq in an approved window and test DNS resolution, DNSSEC and required DHCP leases.
- Retain evidence. Preserve asset and owner identifiers, the applicability decision, before-and-after versions, change approval, installation output, validation results, and any exception or rollback record.
Operational Cautions
Plan for DNS and DHCP availability during restart and preserve lease/configuration evidence. Limit service reachability to intended clients while arranging the supported update.
Evidence To Retain
- Exact product, release stream, package or application version, enabled feature, environment, and accountable owner.
- UTC timestamps, authority revision, approved change record, installer or package-manager output, and resulting version.
- Relevant logs and monitoring evidence, test results, exceptions, compensating controls, and rollback decisions.
Related TechGeeks Resources
Authoritative References
Correction policy: If the authority changes affected versions, fixed versions, severity, exploitation information, mitigations, or required action, TechGeeks will update this notice and its verification date.
Advisory facts are attributed to Red Hat Inc. The linked CSAF content is licensed under CC BY 4.0; TechGeeks operational guidance is summarized for this notice.
