CVE-2026-6507
Dnsmasq: dnsmasq: denial of service due to out-of-bounds write in dhcp bootreply processing
- 7.5HighCVSS base score
- 0.48%Exploitation in 30 daysEPSS · top 58% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
A flaw was found in dnsmasq. A remote attacker could exploit an out-of-bounds write vulnerability by sending a specially crafted BOOTREPLY (Bootstrap Protocol Reply) packet to a dnsmasq server configured with the `--dhcp-split-relay` option. This can lead to memory corruption, causing the dnsmasq daemon to crash and resulting in a denial of service (DoS).
Timeline
ID reserved
By redhat
Published
- 7 months later
· 7 months 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 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVDNVD · Awaiting Analysis | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.48% · top 58% of all CVEs (12 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.5.
Affected products
dnsmasq
- affected 2.92 – < 2.93
Red Hat · Red Hat Enterprise Linux 10
All versions: unaffected
Red Hat · Red Hat Enterprise Linux 6
All versions: unaffected
Red Hat · Red Hat Enterprise Linux 7
All versions: unaffected
Red Hat · Red Hat Enterprise Linux 8
All versions: unaffected
Red Hat · Red Hat Enterprise Linux 9
All versions: unaffected
Red Hat · Red Hat OpenShift Container Platform 4
All versions: unaffected
Red Hat · Red Hat OpenShift Container Platform 4
All versions: unaffected
What to do
Workaround: To mitigate this issue, ensure that the `dnsmasq` service is not configured with the `--dhcp-split-relay` option. If this option is currently in use, remove it from the `dnsmasq` configuration. After modifying the configuration, the `dnsmasq` service must be restarted for the changes to take effect. This may temporarily interrupt DHCP and DNS services provided by `dnsmasq`.
References
References2
- https://access.redhat.com/security/cve/CVE-2026-6507 (opens in a new tab)vdb-entryx_refsource_REDHAT
- RHBZ#2459181 (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)
- EUVD EUVD-2026-23419 (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://cveledger.app/cve/CVE-2026-6507)Record last updated .