CVE-2026-32281 Inefficient policy validation in crypto/x509
Attackers can cause denial of service by forcing inefficient policy validation in Go's crypto/x509 library using certificates with many policy mappings.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-32281?
CVE-2026-32281 is a high-severity denial of service vulnerability in Golang Go, published on 8 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Validating certificate chains which use policies is unexpectedly inefficient when certificates in the chain contain a very large number of policy mappings, possibly causing denial of service. This only affects validation of otherwise trusted certificate chains, issued by a root CA in the VerifyOptions.Roots CertPool, or in the system certificate pool.
Weakness: CWE-295
Which versions are affected by CVE-2026-32281?
2 open source packages ship an affected version, including golang and stdlib. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
golang Bitnami | All versions | 1.25.9, 1.26.2 |
stdlib Go | All versions | 1.25.9, 1.26.2 |
Linux distribution packages (10)
golang-github-openprinting-ipp-usb Red Hat:enterprise_linux:10.2 | All versions | 0:0.9.27-7.el10_2.1 |
ipp-usb Red Hat:enterprise_linux:10.2 | All versions | 0:0.9.27-7.el10_2.1 |
osbuild-composer Red Hat:enterprise_linux_eus:10.0 | All versions | 0:134.1-8.el10_0 |
osbuild-composer-core Red Hat:enterprise_linux_eus:10.0 | All versions | 0:134.1-8.el10_0 |
osbuild-composer-core-debuginfo Red Hat:enterprise_linux_eus:10.0 | All versions | 0:134.1-8.el10_0 |
osbuild-composer-debugsource Red Hat:enterprise_linux_eus:10.0 | All versions | 0:134.1-8.el10_0 |
osbuild-composer-tests-debuginfo Red Hat:enterprise_linux_eus:10.0 | All versions | 0:134.1-8.el10_0 |
osbuild-composer-worker Red Hat:enterprise_linux_eus:10.0 | All versions | 0:134.1-8.el10_0 |
osbuild-composer-worker-debuginfo Red Hat:enterprise_linux_eus:10.0 | All versions | 0:134.1-8.el10_0 |
golang-github-openprinting-ipp-usb Rocky Linux:10 | All versions | 0:0.9.27-7.el10_2.1 |
Products include Golang Go.
How do I fix CVE-2026-32281?
Upgrade golang to a fixed version for your release line: 1.25.9 or 1.26.2.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-32281 being exploited?
There is no known exploitation of CVE-2026-32281 in the wild and no public exploit code.
Other vulnerabilities in Golang Go
- CVE-2020-0601 Microsoft Windows CryptoAPI Spoofing
- CVE-2026-27143 Missing bound checks can lead to memory corruption in safe Go in cmd/compile
- CVE-2024-24790 Unexpected behavior from Is methods for IPv4-mapped IPv6 addresses in net/netip
- CVE-2023-39320 Arbitrary code execution via go.mod toolchain directive in cmd/go
- CVE-2023-24540 Improper handling of JavaScript whitespace in html/template
Sources
Also known as AZL-98793, BELL-CVE-2026-32281, BIT-golang-2026-32281, CLEANSTART-2026-FK38157, CLEANSTART-2026-GR33077, CLEANSTART-2026-LC87549 and 657 more.