How severe is GHSA-5cgq-3rg8-m6cv?

GHSA-5cgq-3rg8-m6cv has a CVSS score of 9.1/10, rated CRITICAL. Immediate patching is strongly recommended.

Which packages are affected by GHSA-5cgq-3rg8-m6cv?

GHSA-5cgq-3rg8-m6cv affects the following packages: golang.org/x/crypto (Go). Ecosystems affected: Go.

How do I fix GHSA-5cgq-3rg8-m6cv?

Update golang.org/x/crypto to 0.52.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-5cgq-3rg8-m6cv is resolved across your whole dependency graph.

How do I detect GHSA-5cgq-3rg8-m6cv in my Go dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for golang.org/x/crypto, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate GHSA-5cgq-3rg8-m6cv if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Is GHSA-5cgq-3rg8-m6cv actively exploited in the wild?

No public exploit code has been indexed for GHSA-5cgq-3rg8-m6cv yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for GHSA-5cgq-3rg8-m6cv?

GHSA-5cgq-3rg8-m6cv has an EPSS (Exploit Prediction Scoring System) score of 6.9%, placing it in the 94th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is GHSA-5cgq-3rg8-m6cv?

GHSA-5cgq-3rg8-m6cv is classified as CWE-295 (CWE-295). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-5cgq-3rg8-m6cv published, and has it been updated?

GHSA-5cgq-3rg8-m6cv was published on June 25, 2026 and was last updated on September 10, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐹

🐹 Go

Not in CISA KEV

CRITICAL severity

golang.org/x/crypto vulnerable to auth bypass via unenforced @revoked statusGHSA-5cgq-3rg8-m6cv

CRITICAL

GHSA-5cgq-3rg8-m6cv is a critical-severity (CVSS 9.1) CWE-295 vulnerability in golang.org/x/crypto. A fix is available for golang.org/x/crypto — see the affected versions and patch details below.

Also known asCVE-2026-42508GO-2026-5021

Published

Jun 25, 2026

Updated

Sep 10, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Oct 24, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
A successful exploit gives an attacker total control of the affected component, not partial access.
CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for GHSA-5cgq-3rg8-m6cv.

EPSS Exploitation Probability

via FIRST.org ↗

6.9%probability of exploitation in next 30 days

Lower Risk+6.26%

Lower risk than most CVEs94th percentile — riskier than 94% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

GHSA-5cgq-3rg8-m6cv by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 395,249 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.

Real-World Exposure

1 pkg affected

🐹golang.org/x/crypto

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.

Description

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.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`golang.org/x/crypto`	all versions	0.52.0`go get golang.org/x/crypto@v0.52.0`

Affected Products

1 product · 1 configurations

Application

cryptogolang

< 0.52.0

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for golang.org/x/crypto, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update golang.org/x/crypto to 0.52.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-5cgq-3rg8-m6cv is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatImportant

Important: A flaw in `golang.org/x/crypto/ssh/knownhosts` allows a remote attacker to bypass security checks. This vulnerability arises because the system fails to properly verify the revocation status of a Certificate Authority (CA) `SignatureKey`. In Red Hat environments, this could enable an attacker to present a…

Workaround published by Red Hat

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

Source: Red Hat security advisory for GHSA-5cgq-3rg8-m6cv (CC BY 4.0)

Product	Fixed in	Advisory
Red Hat Enterprise Linux 10	`podman-7:5.8.2-4.el10_2`	RHSA-2026:37072
Red Hat Enterprise Linux 8	`container-tools:rhel8-8100020260701102925.afee755d`	RHSA-2026:35833
Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support	`container-tools:rhel8-8060020260803064027.ad008a3a`	RHSA-2026:51288
Red Hat Enterprise Linux 8.8 Telecommunications Update Service	`container-tools:rhel8-8080020260721142025.63b34585`	RHSA-2026:49944
Red Hat Enterprise Linux 9	`podman-6:5.8.2-4.el9_8`	RHSA-2026:37123
Red Hat Enterprise Linux 9.6 Extended Update Support	`podman-5:5.4.0-22.el9_6.5`	RHSA-2026:67450
RHEM 1.0 for RHEL 9	`flightctl-0:1.0.3-1.el9em`	RHSA-2026:36796
RHEM 1.1 for RHEL 10	`flightctl-0:1.1.3-1.el10em`	RHSA-2026:41019

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