CVE-2026-42508: Previously, a revoked 'SignatureKey' belonging to a CA was not correctly checked for revocation

Q: How do I fix CVE-2026-42508?

crypto: upgrade to 0.52.0. Exact commands for each OS are on this page.

Q: Is CVE-2026-42508 being exploited?

CVE-2026-42508 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2026-42508 affect?

CVE-2026-42508 affects crypto. Severity is critical (CVSS 9.1). Previously, a revoked 'SignatureKey' belonging to a CA was not correctly checked for revocation. Now, both the 'key' and 'key.SignatureKey' are checked for @revoked.

Q: How urgent is CVE-2026-42508?

Priority 63/100. Critical severity; EPSS top 6%: very likely to be exploited; CISA SSVC: automatable with total technical impact; Remotely exploitable, no login, no user action

This week

CRITICAL 9.1REMOTEUPGRADE

CVE-2026-42508 is a critical-severity flaw (CVSS 9.1) affecting crypto. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Previously, a revoked 'SignatureKey' belonging to a CA was not correctly checked for revocation. Now, both the 'key' and 'key.SignatureKey' are checked for @revoked.

Why this priority

Critical severity
EPSS top 6%: very likely to be exploited
CISA SSVC: automatable with total technical impact
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	9.1 (Critical)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	6.9% (top 6%)
CISA exploited list	No
Weakness	CWE-295
Published	2026-05-22
Last modified	2026-09-15

Publisher (CNA): Go Project · Vendor: golang

Last updated 2026-09-15 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-05-22 04:16 UTCPublished CVE record published
2026-09-15 12:17 UTCUpdated Record last modified

golang crypto UPGRADE

Affected: < 0.52.0

Fixed in: 0.52.0

Safe to downgrade to: no unaffected older release

1. Check installed version

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

2. UPGRADE to 0.52.0 (Debian / Ubuntu)

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

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade crypto

Note

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

Exact fixes by distribution

Go · golang.org/x/crypto · FIXED · 0.52.0 · vulnerable: < 0.52.0 · source

go get golang.org/x/crypto@v0.52.0 go list -m golang.org/x/crypto

Fedora ELN · clash-meta · FIXED · 1.19.33-1.eln159 · FEDORA-2026-7dfb64c5e1 · source

sudo dnf upgrade --advisory=FEDORA-2026-7dfb64c5e1

Fedora 46 · vulkan-utility-libraries · FIXED · 1.4.363.0-1.fc46 · FEDORA-2026-994176daf5 · source

sudo dnf upgrade --advisory=FEDORA-2026-994176daf5

Debian 12 · golang-go.crypto · NO FIX YET

Debian 13 · golang-go.crypto · NO FIX YET

RHEL 10 · podman · FIXED · podman-5.8.2-4.el10_2

sudo dnf upgrade --advisory=RHSA-2026:37072 rpm -q podman

RHEL 9 · podman · FIXED · podman-5.8.2-4.el9_8

sudo dnf upgrade --advisory=RHSA-2026:37123 rpm -q podman

RHEL 9.6 Extended Update Support · podman · FIXED · podman-5.4.0-22.el9_6.5

sudo dnf upgrade --advisory=RHSA-2026:67450 rpm -q podman

RHEL 10 · golang · NOT AFFECTED

RHEL 10 · gvisor-tap-vsock · NO FIX YET

Amazon Linux 2023 · see advisory · FIXED · ALAS2023-2026-1952 · source

sudo dnf update --advisory=ALAS2023-2026-1952

Amazon Linux 2 · see advisory · FIXED · ALAS2-2026-3809 · source

sudo yum update --advisory=ALAS2-2026-3809

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-2026-42508?

crypto: upgrade to 0.52.0. Exact commands for each OS are on this page.

Is CVE-2026-42508 being exploited?

CVE-2026-42508 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-2026-42508 affect?

CVE-2026-42508 affects crypto. Severity is critical (CVSS 9.1). Previously, a revoked 'SignatureKey' belonging to a CA was not correctly checked for revocation. Now, both the 'key' and 'key.SignatureKey' are checked for @revoked.

How urgent is CVE-2026-42508?

Priority 63/100. Critical severity; EPSS top 6%: very likely to be exploited; CISA SSVC: automatable with total technical impact; Remotely exploitable, no login, no user action

Software pages

Go (Golang) vulnerabilities

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References

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