CVE-2026-93009

A flaw was found in dnsmasq. The DHCPv6 client hostname parser can read one byte past the end of a crafted FQDN option because it checks the next label length before confirming the pointer is still inside the option. An attacker on the local network can trigger this with a single DHCPv6 packet. The extra byte is not returned to the client or logged, and no crash has been demonstrated.

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/security/cve/CVE-2026-93009
https://bugzilla.redhat.com/show_bug.cgi?id=2536083

Configurations

No configuration.

History

29 Oct 2026, 14:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-29 14:18

Updated : 2026-10-30 08:17

NVD link : CVE-2026-93009

Mitre link : CVE-2026-93009

CVE.ORG link : CVE-2026-93009

JSON object : View

Products Affected

No product.

CWE

CWE-125

Out-of-bounds Read

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