How severe is CVE-2026-43989?

CVE-2026-43989 has a CVSS 3.x base score of 8.5, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability low.

Is CVE-2026-43989 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (4th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-43989?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-43989 have an EU (EUVD) identifier?

Yes. CVE-2026-43989 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-29538.

When was CVE-2026-43989 published?

CVE-2026-43989 was published on 2026-05-12 and last updated on 2026-06-17.

CVE-2026-43989

CVE-2026-43989 is a high-severity vulnerability with a CVSS 3.x base score of 8.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: High (CVSS 3.x base score 8.5)
EPSS exploit prediction: 0% (4th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-29538
Weakness: CWE-20
Published: 2026-05-12
Last modified: 2026-06-17

Description

JunoClaw is an agentic AI platform built on Juno Network. Prior to 0.x.y-security-1, the upload_wasm MCP tool accepted a filesystem path from the agent and uploaded whatever bytes the path resolved to, with no validation of location, symlink target, file size, or file format. This vulnerability is fixed in 0.x.y-security-1.

Frequently asked questions

What is CVE-2026-43989?: JunoClaw is an agentic AI platform built on Juno Network. Prior to 0.x.y-security-1, the upload_wasm MCP tool accepted a filesystem path from the agent and uploaded whatever bytes the path resolved to, with no validation of location, symlink target, file size, or file format. This vulnerability is fixed in 0.x.y-security-1.
How severe is CVE-2026-43989?: CVE-2026-43989 has a CVSS 3.x base score of 8.5, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability low.
Is CVE-2026-43989 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (4th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-43989?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-43989 have an EU (EUVD) identifier?: Yes. CVE-2026-43989 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-29538.
When was CVE-2026-43989 published?: CVE-2026-43989 was published on 2026-05-12 and last updated on 2026-06-17.

References

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