CVE-2026-6507 Dnsmasq: dnsmasq: denial of service due to out-of-bounds write in dhcp bootreply processing
Remote attackers can cause denial of service in dnsmasq via crafted BOOTREPLY packets when dhcp-split-relay is enabled.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-6507?
CVE-2026-6507 is a high-severity memory corruption vulnerability in Red Hat Enterprise Linux 10, published on 17 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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).
Weakness: CWE-787
Which versions are affected by CVE-2026-6507?
Linux distribution packages (1)
dnsmasq openSUSE:Tumbleweed | All versions | 2.92-3.1 |
How do I fix CVE-2026-6507?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-6507 being exploited?
There is no known exploitation of CVE-2026-6507 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-6507, GHSA-28hj-3gj2-63m5, UBUNTU-CVE-2026-6507, USN-8308-1, openSUSE-SU-2026:10605-1.