CVE-2026-32281: Validating certificate chains which use policies is unexpectedly inefficient when certificates in the chain co

Routine

HIGH 7.5REMOTEUPGRADE

CVE-2026-32281 is a high-severity flaw (CVSS 7.5) affecting go. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

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.

Why this priority

High severity
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	7.5 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.4% (top 71%)
CISA exploited list	No
Weakness	CWE-295
Published	2026-04-08
Last modified	2026-07-25

Publisher (CNA): Go Project · Vendor: golang

Last updated 2026-07-25 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-04-08 02:16 UTCPublished CVE record published
2026-07-25 10:10 UTCUpdated Record last modified

golang go UPGRADE

Affected: < 1.25.9 · >= 1.26.0 and < 1.26.2

Fixed in: 1.25.9, 1.26.2

Safe to downgrade to: a release before 1.26.0

1. Check installed version

apt-cache policy go || rpm -q go || go --version

2. UPGRADE to 1.25.9 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade go

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade go

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 1.26.0 (Debian / Ubuntu)

apt-cache madison go sudo apt install go=<VERSION_BEFORE_1.26.0> sudo apt-mark hold go

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list go sudo dnf downgrade go-<VERSION_BEFORE_1.26.0> sudo dnf versionlock add go

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Advisories and coverage

Official advisories

AlmaLinux Errata: [ALSA-2026:29703] Important: containernetworking-plugins security update 2026-06-29
AlmaLinux Errata: [ALSA-2026:29702] Important: runc security update 2026-06-29
AlmaLinux Errata: [ALSA-2026:29455] Important: buildah security update 2026-06-25
AlmaLinux Errata: [ALSA-2026:28074] Important: skopeo security update 2026-06-23
AlmaLinux Errata: [ALSA-2026:26447] Important: podman security update 2026-06-17

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-32281?

go: upgrade to 1.25.9, 1.26.2. Exact commands for each OS are on this page.

Is CVE-2026-32281 being exploited?

CVE-2026-32281 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-32281 affect?

CVE-2026-32281 affects go. Severity is high (CVSS 7.5). 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 truste

How urgent is CVE-2026-32281?

Priority 39/100. High severity; Remotely exploitable, no login, no user action

Software pages

Go (Golang) vulnerabilities

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References

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