CVE-2026-93008
Dnsmasq: dnsmasq: out-of-bailiwick cache injection through cname chase in split-dns configurations
- Published
- Updated
- Reserved
- Assigned by
- redhat
Description
A flaw was found in dnsmasq. When following a CNAME in a DNS response, the resolver can cache records for the CNAME target without checking that those records belong to the responding server's authorized zone. In split-DNS deployments that send some domains to a specific upstream, an attacker who controls that upstream can inject cache entries for unrelated names. Later clients may then receive attacker-chosen addresses for those names.
Timeline
ID reserved
By redhat
- 42 days later
· 42 days later
Published
- 7 days later
· 7 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| redhatCNA (assigner) | 3.1 | Medium6.8 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:H/A:N |
| NVDNVD · Awaiting Analysis | 3.1 | Medium6.8 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:H/A:N |
- EPSS (exploitation in 30 days)
- 0.15% · top 96% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.8.
Weakness
Affected products
Red Hat · Red Hat Ceph Storage 9
All versions: affected
Red Hat · Red Hat Enterprise Linux 10
All versions: affected
Red Hat · Red Hat Enterprise Linux 6
All versions: affected
Red Hat · Red Hat Enterprise Linux 7
All versions: affected
Red Hat · Red Hat Enterprise Linux 8
All versions: affected
Red Hat · Red Hat Enterprise Linux 9
All versions: affected
Red Hat · Red Hat OpenShift Container Platform 4
All versions: affected
Red Hat · Red Hat OpenShift Container Platform 4
All versions: affected
Red Hat · Red Hat OpenShift Container Platform 4
All versions: affected
Red Hat · Red Hat OpenShift Container Platform 4
All versions: affected
Red Hat · Red Hat OpenShift Container Platform 5
All versions: affected
Red Hat · Red Hat OpenShift Container Platform 5
All versions: affected
Red Hat · Red Hat OpenStack Platform 13 (Queens)
All versions: affected
Red Hat · Red Hat OpenStack Platform 18.0
All versions: affected
What to do
Workaround: The following measures reduce risk: 1. Do not point server=/domain/ at untrusted or attacker-reachable DNS servers. 2. Restrict dnsmasq to communicate only with trusted upstream resolvers at the firewall. 3. For local=/domain/ zones, define all names that should be served locally. 4. Do not rely on --dnssec to mitigate this for unsigned zones. Insecure records are still cached.
References (2)
- https://access.redhat.com/security/cve/CVE-2026-93008 (opens in a new tab)vdb-entryx_refsource_REDHAT
- RHBZ#2536079 (opens in a new tab)issue-trackingx_refsource_REDHAT
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-93008)Record last updated .