Memory Corruption Vulnerability in Go DNS Resolver by Google
CVE-2026-33811

7.5HIGH

Key Information:

Vendor

Go Standard Library

Status
Net
Vendor
CVE Published:
7 May 2026

What is CVE-2026-33811?

A vulnerability exists in the Go DNS resolver when utilizing LookupCNAME, wherein an excessively lengthy CNAME response can lead to a double-free of C memory, resulting in potential application crashes. This flaw underscores the importance of proper memory management in network operations, as it could disrupt service availability and create security risks.

Affected Version(s)

net 0 < 1.25.10

net 1.26.0-0 < 1.26.3

References

https://go.dev/issue/78803
https://go.dev/cl/767860
https://groups.google.com/g/golang-announce/c/qcCIEXso47M

CVSS V3.1

Score:
7.5
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

hamayanhamayan
.