high7.5
CVE-2026-33811
When using LookupCNAME with the cgo DNS resolver, a very long CNAME response can trigger a double-free of C memory and a crash.
Impact
When using LookupCNAME with the cgo DNS resolver, a very long CNAME response can trigger a double-free of C memory and a crash.
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Golang | Go | before 1.25.10 from 1.26.0 before 1.26.3 |
Weakness classification
References
- NVD record
- CVE.org record
- 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://access.redhat.com/errata/RHSA-2026:22112
- https://access.redhat.com/errata/RHSA-2026:22120
- https://access.redhat.com/errata/RHSA-2026:22121
- 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