Heap Overflow Vulnerability in Dnsmasq by Red Hat
CVE-2026-93011

5.3MEDIUM

Key Information:

Vendor

Red Hat
Status
Red Hat Ceph Storage 9
Red Hat Enterprise Linux 10
Red Hat Enterprise Linux 6
Red Hat Enterprise Linux 7
Vendor
CVE Published:
29 October 2026

What is CVE-2026-93011?

A vulnerability exists in Dnsmasq that allows an attacker to exploit the DNSSEC validator functionality. If the server processes a specially crafted DNSSEC response, it may lead to a heap overflow condition by writing past the allocated memory boundaries. This flaw arises after a modification of internal domain-name buffer sizes and can lead to the corruption of adjacent heap metadata. Although DNSSEC support is not enabled by default, should it be activated, potential attackers may leverage this vulnerability to compromise the server's integrity.

References

https://access.redhat.com/security/cve/CVE-2026-93011
vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2536082
issue-trackingx_refsource_REDHAT

CVSS V3.1

Score:
5.3
Severity:
MEDIUM
Confidentiality:
None
Integrity:
Low
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Red Hat would like to thank Shubham Raj (Causal Security) for reporting this issue.
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