Is CVE-2026-42421 in the CISA KEV catalog?

No. CVE-2026-42421 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2026-42421?

CVE-2026-42421 has a CVSS v3 base score of 5.4 (MEDIUM).

What is the EPSS score for CVE-2026-42421?

CVE-2026-42421 has an EPSS score of 0.19% (8th percentile), estimating the probability of exploitation in the next 30 days.

How do I fix CVE-2026-42421?

Upgrade openclaw to 2026.4.8 or later.

CVE & CISA-KEV Catalog

CVE-2026-42421

MEDIUM

5.4

CVSS v3

NVD

Description

OpenClaw before 2026.4.8 contains a session management vulnerability where existing WebSocket sessions survive shared gateway token rotation. Attackers can maintain unauthorized access to WebSocket connections after token rotation by exploiting the failure to disconnect existing shared-token sessions.

CWE-613

How to fix

Remediation Available

openclawNVD

Affected:< 2026.4.8Fixed in:2026.4.8CVE-2026-42421derived from NVD

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredLow

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityLow

IntegrityLow

AvailabilityNone

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

Exploit Intelligence

0.19%probability of exploitation in 30 days

8thpercentile

Low risk: more likely to be exploited than 8% of all known CVEs.

References

Patch1

github.com

Vendor Advisory1

github.com

Third-Party Advisory1

vulncheck.com

Embed a live status badge for CVE-2026-42421

Markdown

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HTML

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-04-30.