CVE-2026-6507 | Dnsmasq: dnsmasq: denial of service due to out-of-bounds write in dhcp bootreply processing

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).

Published: 2026-04-17 Last update: 2026-04-17 Assigner: [email protected] Source: [email protected]
NVD Status：Awaiting Analysis，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-6507 is rated Low Risk (33.3/100): CVSS High severity, with low exploitation likelihood (EPSS 0.03%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-6507

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-04-21 0.11% 0.03% -0.07%
2 2026-04-18 — 0.11% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-6507

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]

Weakness enumeration for CVE-2026-6507

GitHub Security Advisory for CVE-2026-6507

GHSA-28hj-3gj2-63m5 · Severity: high — A flaw was found in dnsmasq. A remote attacker could exploit an out-of-bounds write vulnerability...

OS Trackers for CVE-2026-6507

vendor priority summary link
debian unimportant CVE-2026-6507 unimportant priority: Debian including 1 source packages (dnsmasq), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2026-6507
redhat medium — https://access.redhat.com/security/cve/CVE-2026-6507
suse high CVE-2026-6507 severity important: SUSE including 2 source package names (dnsmasq, dnsmasq-utils), 30 product×package rows across 27 product lines (SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS, SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS, … (27 product lines)): Known Not Affected 30. https://www.suse.com/security/cve/CVE-2026-6507/
ubuntu medium CVE-2026-6507 medium priority: Ubuntu including 1 source packages (dnsmasq), 9 status rows across 9 suites (bionic, focal, jammy, noble, questing, resolute, trusty, upstream, xenial): not-affected 7, needed 1, released 1. https://ubuntu.com/security/CVE-2026-6507

Affected software / configurations for CVE-2026-6507

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-6507

cvelogic Threat Intelligence