How severe is CVE-2026-5321?

CVE-2026-5321 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2026-5321 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (6th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-5321?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-5321 have an EU (EUVD) identifier?

Yes. CVE-2026-5321 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-18122.

When was CVE-2026-5321 published?

CVE-2026-5321 was published on 2026-04-02 and last updated on 2026-06-17.

CVE-2026-5321

CVE-2026-5321 is a medium-severity vulnerability with a CVSS 3.x base score of 4.3. 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-346.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
CVSS v2: 4.0
CVSS v4: 2.1
EPSS exploit prediction: 0% (6th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-18122
Weakness: CWE-346
Published: 2026-04-02
Last modified: 2026-06-17

Description

A flaw has been found in vanna-ai vanna up to 2.0.2. Affected by this issue is some unknown functionality of the component FastAPI/Flask Server. Executing a manipulation can lead to permissive cross-domain policy with untrusted domains. The attack can be launched remotely. The exploit has been published and may be used. The vendor was contacted early about this disclosure but did not respond in any way.

Frequently asked questions

What is CVE-2026-5321?: A flaw has been found in vanna-ai vanna up to 2.0.2. Affected by this issue is some unknown functionality of the component FastAPI/Flask Server. Executing a manipulation can lead to permissive cross-domain policy with untrusted domains. The attack can be launched remotely. The exploit has been published and may be used. The vendor was contacted early about this disclosure but did not respond in any way.
How severe is CVE-2026-5321?: CVE-2026-5321 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2026-5321 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (6th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-5321?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-5321 have an EU (EUVD) identifier?: Yes. CVE-2026-5321 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-18122.
When was CVE-2026-5321 published?: CVE-2026-5321 was published on 2026-04-02 and last updated on 2026-06-17.

References

Other CWE-346 vulnerabilities

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