CVE-2026-33811
Published: May 13, 2026Last modified: May 16, 2026
Description
When using LookupCNAME with the cgo DNS resolver, a very long CNAME response can trigger a double-free of C memory and a crash.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 7.5 |
| Attack Vector | NETWORK |
| Attack complexity | LOW |
| Privileges required | NONE |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | NONE |
| Integrity impact | NONE |
| Availability impact | HIGH |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | go | Fixed (1.25.10-r0) |
| 25 LTS | go | Fixed (1.25.10-r0) | |
| Stream | go | Fixed (1.26.3-r0) | |
| Hardened Containers | 23 LTS | go | Fixed (1.25.10-r0) |
| 25 LTS | go | Fixed (1.25.10-r0) | |
| Stream | go | Fixed (1.26.3-r0) |
References
- https://access.redhat.com/errata/RHSA-2026:23262
- https://access.redhat.com/errata/RHSA-2026:23264
- https://access.redhat.com/errata/RHSA-2026:33120
- https://access.redhat.com/errata/RHSA-2026:33123
- https://access.redhat.com/errata/RHSA-2026:33142
- https://access.redhat.com/errata/RHSA-2026:33150
- https://access.redhat.com/errata/RHSA-2026:33574
- https://access.redhat.com/errata/RHSA-2026:34357
- https://access.redhat.com/errata/RHSA-2026:34359
- https://access.redhat.com/errata/RHSA-2026:34364
- https://access.redhat.com/errata/RHSA-2026:35832
- https://access.redhat.com/errata/RHSA-2026:35993
- https://access.redhat.com/errata/RHSA-2026:35994
- https://access.redhat.com/errata/RHSA-2026:35995
- https://access.redhat.com/errata/RHSA-2026:36207
- https://access.redhat.com/errata/RHSA-2026:36319
- https://access.redhat.com/errata/RHSA-2026:36617
- https://access.redhat.com/errata/RHSA-2026:36625
- https://access.redhat.com/errata/RHSA-2026:36648
- https://access.redhat.com/errata/RHSA-2026:36651
- https://access.redhat.com/errata/RHSA-2026:36776
- https://access.redhat.com/errata/RHSA-2026:36796
- https://access.redhat.com/errata/RHSA-2026:36797
- https://access.redhat.com/security/cve/CVE-2026-33811
- https://bugzilla.redhat.com/show_bug.cgi?id=2467822
- https://go.dev/cl/767860
- https://go.dev/issue/78803
- https://groups.google.com/g/golang-announce/c/qcCIEXso47M
- https://pkg.go.dev/vuln/GO-2026-4981
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33811.json