No exploitation reportedFix available

CVE-2026-32280

Q: Is CVE-2026-32280 actively exploited?

Active exploitation of CVE-2026-32280 has not been confirmed. Its EPSS score was 0.6% on 2026-10-22, the estimated probability of exploitation in the next 30 days.

Q: What is the CVSS score for CVE-2026-32280?

CVE-2026-32280 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Unexpected work during chain building in crypto/x509

No exploitation reported by the sources we read.

Published2026-04-08
Fixed in1.26.2 · 1.25.9
WeaknessCWE-770

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

During chain building, the amount of work that is done is not correctly limited when a large number of intermediate certificates are passed in VerifyOptions.Intermediates, which can lead to a denial of service. This affects both direct users of crypto/x509 and users of crypto/tls.

Timeline

dates in UTC

2026-04-0802:16CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 21:37 UTC

Indicators tagged with this CVE, per day0 indicators over 7 days

Block these indicators

Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2026-32280?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2026-32280?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD · OSV

Branch	Affected	Fixed in	Source
1.26	≥ 1.26.0, < 1.26.2	1.26.2	NVD
1.26	≥ 1.26.0-0, < 1.26.2	1.26.2	OSV
1.25	< 1.25.9	1.25.9	NVD · OSV

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

aardvark-dnsAlmaLinux:8all versions · fixed in 2:1.10.1-2.module_el8.10.0+3901+4b80ecd7
aardvark-dnsAlmaLinux:8all versions · fixed in 2:1.10.1-2.module_el8.10.0+3909+6e1c1eb7
aardvark-dnsAlmaLinux:8all versions · fixed in 2:1.10.1-2.module_el8.10.0+4047+545787c4
aardvark-dnsAlmaLinux:8all versions · fixed in 2:1.10.1-2.module_el8.10.0+4089+ce72bbbe
buildahAlmaLinux:10all versions · fixed in 2:1.43.1-2.el10_2and 1 other package
buildahAlmaLinux:9all versions · fixed in 2:1.43.1-2.el9_8and 1 other package
buildahAlmaLinux:8all versions · fixed in 2:1.33.14-3.module_el8.10.0+4211+49ea0979and 1 other package
buildah-testsAlmaLinux:8all versions · fixed in 2:1.33.14-3.module_el8.10.0+4136+16425343

77 more package ranges on OSV.dev

Vendor advisories

CVE-2026-32280 Red Hat Product Security4,661 products fixed · 132 known affected
crypto/x509: crypto/tls: golang: Go: Denial of Service vulnerability in certificate chain building
rhai/assisted-installer-rhel9 as a component of Assisted Installer for Red Hat OpenShift Container Platform 2 · compliance/openshift-compliance-rhel8-operator as a component of Compliance Operator · build-of-trustee/trustee-rhel9-operator as a component of Confidential Compute Attestation · +129 more
RHSA-2026:84734 Red Hat Product Security4 products fixed
Red Hat Security Advisory: RHOAI 3.4.5 - Red Hat OpenShift AI
RHSA-2026:82372 Red Hat Product Security4 products fixed
Red Hat Security Advisory: cert-manager Operator for Red Hat OpenShift 1.18.2
RHSA-2026:82354 Red Hat Product Security4 products fixed
Red Hat Security Advisory: cert-manager Operator for Red Hat OpenShift 1.18.2
RHSA-2026:82347 Red Hat Product Security8 products fixed
Red Hat Security Advisory: cert-manager Operator for Red Hat OpenShift 1.18.2
RHSA-2026:76752 Red Hat Product Security2 products fixed
Red Hat Security Advisory: OpenShift Security Profiles Operator bug fix and enhancement update

199 more advisories

Full record on NVD

Fix

Update Go to 1.26.2 · 1.25.9
Vendor fix Red Hat Product Security RHSA-2026:84734 · 4 productsFor Red Hat OpenShift AI 3.4.5 see the following documentation, which will be updated shortly for this release, for important instructions on how to upgrade your cluster and fully apply this errata update: https://docs.redhat.com/en/documentation/red_hat_openshift_ai/
Vendor fix Red Hat Product Security RHSA-2026:82372 · 4 productsBefore applying this update, make sure all previously released errata relevant to your system have been applied. The steps to apply the upgraded images are different depending on the installation plan approval policy you used when installing the cert-manager Operator for Red Hat OpenShift. - If t…
Vendor fix Red Hat Product Security RHSA-2026:76752 · 2 productsBefore applying this update, make sure all previously released errata relevant to your system have been applied. For details on how to apply this update, refer to: https://docs.openshift.com/container-platform/latest/updating/updating_a_cluster/updating-cluster-cli.html
Vendor fix Red Hat Product Security RHSA-2026:74791 · 4 productsFor more information, see the following resources: Documentation - Open Policy Agent Gatekeeper documentation: https://open-policy-agent.github.io/gatekeeper/website/docs/ - Red Hat Gatekeeper Operator documentation: https://docs.redhat.com/en/documentation/red_hat_advanced_cluster_management_for…
Vendor fix Red Hat Product Security RHSA-2026:72805 · 17 productsFor details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
Vendor fix Red Hat Product Security RHSA-2026:65838 · 113 productsFor OpenShift Container Platform 4.13 see the following documentation, which will be updated shortly for this release, for important instructions on how to upgrade your cluster and fully apply this asynchronous errata update: https://docs.redhat.com/en/documentation/openshift_container_platform/4.…

Advisories and patches

go.devPatch
groups.google.comRelease Notes
pkg.go.devVendor Advisory

Detection

Nuclei template: none so far
Exploit-DB: no entry
Proof-of-concept repositories: none listed

Sources

NVDCVE recordread 2026-10-23
CISA-ADPSSVC decisionnone2026-04-08
OpenCVESSVC decisionnone—
CISA-ADPCVSS 3.17.52026-04-08
CNACVSS 3.17.5read 2026-10-23
CISA-ADPweakness (CWE)CWE-7702026-04-08
CNAweakness (CWE)CWE-770read 2026-10-23
FIRST EPSSEPSS score0.6 %2026-10-22
OSVaffected packages—
Microsoft MSRCadvisory—

Technical details

CVSS v3 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Published: 2026-04-08
Last Modified: 2026-09-18
NVD status: Modified
MSRC Title: Unexpected work during chain building in crypto/x509

Frequently asked questions

What is CVE-2026-32280?

Is CVE-2026-32280 actively exploited?

Active exploitation of CVE-2026-32280 has not been confirmed. Its EPSS score was 0.6% on 2026-10-22, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2026-32280?

CVE-2026-32280 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

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