NVD / CVE Program· CNA Go

CVE-2026-32281: Inefficient policy validation in crypto/x509

Noroxi assessment

Priority: Monitor (action score 30/100)

The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
Probability of exploitation in the next 30 days: 0.36% (FIRST EPSS).
Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
According to CISA the attack is automatable: targets can be found by mass scanning.
Fixed version: Go standard library crypto/x509 1.25.9, 1.26.2; cbl2 msft-golang 1.25.8-1 on CBL-Mariner 2.0 Release Notes.

Low priority for now. Upgrade to Go standard library crypto/x509 1.25.9, 1.26.2; cbl2 msft-golang 1.25.8-1 on CBL-Mariner 2.0 Release Notes or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

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.

HighCVSS 7.5 · v3.1—No exploit Fix available

Published: Apr 7, 2026
Updated: Jul 25, 2026
EPSS: 0.3% · 30th percentile
CWE: CWE-295

Report tools

JSON

Action score

Monitor

Low priority for now.

CVSS: 30 / 40 · 7.5 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.3%

CISA SSVC decision

Exploitation: none
Automatable: yes
Technical impact: partial

Vulnrichment: CISA's decision-tree inputs.

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No public exploit code on record
A fix has been released

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Noroxi analysis

What does it mean in your environment?

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

Vendor	Product	CPE
golang	go	cpe:2.3:a:golang:go

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This vulnerability is about certificate validation or weak cryptography. The free SSL checker tests your certificate, enabled TLS versions and weak ciphers.

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Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

golang gobefore 1.25.9
golang go1.26.0 and later · before 1.26.2

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Go). Independent of NVD's CPE analysis and usually ahead of it.

Go standard library crypto/x509
- before 1.25.9affected · semver
- 1.26.0-0 and later · before 1.26.2affected · semver

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

Ecosystem	Package	Affected range	Fix
AlmaLinux:10	buildah	before 2:1.43.1-2.el10_2	2:1.43.1-2.el10_2
AlmaLinux:10	buildah-tests	before 2:1.43.1-2.el10_2	2:1.43.1-2.el10_2
AlmaLinux:10	delve	before 1.26.1-2.el10_2	1.26.1-2.el10_2
AlmaLinux:10	go-fdo-client	before 1.0.0-4.el10_2	1.0.0-4.el10_2
AlmaLinux:10	go-fdo-server	before 1.0.1-2.el10_2	1.0.1-2.el10_2
AlmaLinux:10	go-fdo-server-manufacturer	before 1.0.1-2.el10_2	1.0.1-2.el10_2
AlmaLinux:10	go-fdo-server-owner	before 1.0.1-2.el10_2	1.0.1-2.el10_2
AlmaLinux:10	go-fdo-server-rendezvous	before 1.0.1-2.el10_2	1.0.1-2.el10_2
AlmaLinux:10	opentelemetry-collector	before 0.144.0-2.el10_2	0.144.0-2.el10_2
AlmaLinux:10	osbuild-composer	before 165.1-3.el10_2.1.alma.3	165.1-3.el10_2.1.alma.3
AlmaLinux:10	osbuild-composer-core	before 165.1-3.el10_2.1.alma.3	165.1-3.el10_2.1.alma.3
AlmaLinux:10	osbuild-composer-worker	before 165.1-3.el10_2.1.alma.3	165.1-3.el10_2.1.alma.3
AlmaLinux:10	podman	before 7:5.8.2-3.el10_2.alma.1	7:5.8.2-3.el10_2.alma.1
AlmaLinux:10	podman-docker	before 7:5.8.2-3.el10_2.alma.1	7:5.8.2-3.el10_2.alma.1
AlmaLinux:10	podman-remote	before 7:5.8.2-3.el10_2.alma.1	7:5.8.2-3.el10_2.alma.1
AlmaLinux:10	podman-tests	before 7:5.8.2-3.el10_2.alma.1	7:5.8.2-3.el10_2.alma.1
AlmaLinux:10	skopeo	before 2:1.22.2-2.el10_2	2:1.22.2-2.el10_2
AlmaLinux:10	skopeo-tests	before 2:1.22.2-2.el10_2	2:1.22.2-2.el10_2
AlmaLinux:8	aardvark-dns	before 2:1.10.1-2.module_el8.10.0+4089+ce72bbbe	2:1.10.1-2.module_el8.10.0+4089+ce72bbbe
AlmaLinux:8	aardvark-dns	before 2:1.10.1-2.module_el8.10.0+4047+545787c4	2:1.10.1-2.module_el8.10.0+4047+545787c4
AlmaLinux:8	aardvark-dns	before 2:1.10.1-2.module_el8.10.0+3901+4b80ecd7	2:1.10.1-2.module_el8.10.0+3901+4b80ecd7
AlmaLinux:8	aardvark-dns	before 2:1.10.1-2.module_el8.10.0+3909+6e1c1eb7	2:1.10.1-2.module_el8.10.0+3909+6e1c1eb7
AlmaLinux:8	buildah	before 2:1.33.14-3.module_el8.10.0+4211+49ea0979	2:1.33.14-3.module_el8.10.0+4211+49ea0979
AlmaLinux:8	buildah-tests	before 2:1.33.14-3.module_el8.10.0+4136+16425343	2:1.33.14-3.module_el8.10.0+4136+16425343

+96

Same product

golang: all records

Other highest-scoring records for the same primary product.

CVE-2018-7187The "go get" implementation in Go 1.9.4, when the -insecure command-line option is used, does not validate the import path (get/vcs.go only
54Plan
CVE-2018-16873In Go before 1.10.6 and 1.11.x before 1.11.3, the "go get" command is vulnerable to remote code execution when executed with the -u flag and
52Plan
CVE-2021-38297Go before 1.16.9 and 1.17.x before 1.17.2 has a Buffer Overflow via large arguments in a function invocation from a WASM module, when GOARCH
42Plan

Published before and after this one in the same product

← EarlierCVE-2026-27144Apr 7, 2026 · Miscompilation allows memory corruption via CONVNOP-wrapped array copy in cmd/compile
28Monitor
← EarlierCVE-2026-32280Apr 7, 2026 · Unexpected work during chain building in crypto/x509
30Monitor
Later →CVE-2026-32282Apr 7, 2026 · TOCTOU permits root escape on Linux via Root.Chmod in os in internal/syscall/unix
25Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / package	Fixed version	Source
Go standard library crypto/x509	1.25.9	Vendor (CNA)
Go standard library crypto/x509	1.26.2	Vendor (CNA)
azl3 golang 1.27.0-1 on Azure Linux 3.0	—	Microsoft (MSRC)
cbl2 msft-golang 1.25.8-1 on CBL-Mariner 2.0	Release Notes	Microsoft (MSRC)
almalinux:delve	1.26.1-2.el10_2 · AlmaLinux:10	Package registry (OSV)
almalinux:git-lfs	3.7.1-4.el9_8 · AlmaLinux:9	Package registry (OSV)
almalinux:go-fdo-client	1.0.0-4.el10_2 · AlmaLinux:10	Package registry (OSV)
almalinux:go-fdo-server	1.0.1-2.el10_2 · AlmaLinux:10	Package registry (OSV)
almalinux:go-fdo-server-manufacturer	1.0.1-2.el10_2 · AlmaLinux:10	Package registry (OSV)
almalinux:go-fdo-server-owner	1.0.1-2.el10_2 · AlmaLinux:10	Package registry (OSV)
almalinux:go-fdo-server-rendezvous	1.0.1-2.el10_2 · AlmaLinux:10	Package registry (OSV)
almalinux:opentelemetry-collector	0.144.0-2.el10_2 · AlmaLinux:10	Package registry (OSV)
almalinux:podman	7:5.8.2-3.el10_2.alma.1 · AlmaLinux:10	Package registry (OSV)
almalinux:podman-docker	7:5.8.2-3.el10_2.alma.1 · AlmaLinux:10	Package registry (OSV)
almalinux:podman-plugins	6:5.8.2-3.el9_8 · AlmaLinux:9	Package registry (OSV)
almalinux:podman-remote	7:5.8.2-3.el10_2.alma.1 · AlmaLinux:10	Package registry (OSV)
almalinux:podman-tests	7:5.8.2-3.el10_2.alma.1 · AlmaLinux:10	Package registry (OSV)
alpine:go	1.25.9-r0 · Alpine:v3.23	Package registry (OSV)
alpine:rclone	1.73.5-r0 · Alpine:v3.24	Package registry (OSV)
debian:golang-1.25	1.25.9-1 · Debian:14	Package registry (OSV)
debian:golang-1.26	1.26.2-1 · Debian:14	Package registry (OSV)
Go:stdlib	1.25.9	Package registry (OSV)
Go:stdlib	1.26.2	Package registry (OSV)
opensuse:go1.25	1.25.9-1.1 · openSUSE:Tumbleweed	Package registry (OSV)
opensuse:go1.25-openssl	1.25.12-160000.1.1 · openSUSE:Leap 16.0	Package registry (OSV)
opensuse:go1.26	1.26.2-1.1 · openSUSE:Tumbleweed	Package registry (OSV)
opensuse:go1.26-openssl	1.26.4-160000.1.1 · openSUSE:Leap 16.0	Package registry (OSV)
red hat:go-toolset	0:1.25.9-3.el10_1 · Red Hat:enterprise_linux:10.1	Package registry (OSV)
red hat:golang	0:1.25.9-3.el10_1 · Red Hat:enterprise_linux:10.1	Package registry (OSV)
red hat:golang-bin	0:1.25.9-3.el10_1 · Red Hat:enterprise_linux:10.1	Package registry (OSV)

+25

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

Jakub Ciolek - https://ciolek.dev

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

CVE-2025-6812161 days apartUnexpected session resumption in crypto/tls
40Plan
CVE-2026-338100 days apartCase-sensitive excludedSubtrees name constraints cause Auth Bypass in crypto/x509
32Monitor
CVE-2026-2713732 days apartIncorrect enforcement of email constraints in crypto/x509
30Monitor
CVE-2025-61729126 days apartExcessive resource consumption when printing error string for host certificate validation in crypto/x509
30Monitor
CVE-2025-58188160 days apartPanic when validating certificates with DSA public keys in crypto/x509
30Monitor
CVE-2025-61727125 days apartImproper application of excluded DNS name constraints when verifying wildcard names in crypto/x509
26Monitor

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

Anyone who can reach it over the internet can trigger it.
No account or password is required.
No user action is required.
No special conditions are required; it is repeatable.

If successful

Confidentiality: none
Integrity: none
Availability: high · the service can be disrupted

Attack vector: Network
Attack complexity: Low
Privileges required: None
User interaction: None
Scope: Unchanged
Confidentiality impact: None
Integrity impact: None
Availability impact: High

Weakness class (CWE)

CWE-295 · Improper Certificate Validation

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

nvd-primary

Root cause

A certificate validation error is silently swallowed instead of terminating the connection. Often, code added for a test environment makes its way into production.

The bug in code

The whole CWE-295 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

kotlin

1override fun checkServerTrusted(chain: Array<X509Certificate>, type: String) {
2  // Left empty for the test environment
3}

Fixed

kotlin

1val client = OkHttpClient.Builder()
2  .certificatePinner(
3    CertificatePinner.Builder()
4      .add("api.sirius.example", "sha256/…")
5      .build()
6  ).build()

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Attack patterns (CAPEC)

ATT&CK techniques

—

Change log

Fix✗ → ✓Sep 28, 2026, 10:10 PM UTC

For records you follow, these changes also arrive as notifications. →

References

go.dev/cl/758061

Show all references (3 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records