How severe is CVE-2026-53947?

CVE-2026-53947 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2026-53947 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (11th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-53947?

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

Does CVE-2026-53947 have an EU (EUVD) identifier?

Yes. CVE-2026-53947 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-39022.

When was CVE-2026-53947 published?

CVE-2026-53947 was published on 2026-06-24 and last updated on 2026-06-25.

CVE-2026-53947

CVE-2026-53947 is a medium-severity vulnerability with a CVSS 3.x base score of 5.3. 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-204.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
EPSS exploit prediction: 0% (11th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-39022
Weakness: CWE-204
Published: 2026-06-24
Last modified: 2026-06-25

Description

Ghost is a Node.js content management system. From 5.18.0 until 6.21.1, a discrepancy in responses from the members signin endpoints made it possible for an unauthenticated attacker to determine whether a given email address belongs to a registered member of a Ghost site. This vulnerability is fixed in 6.21.1.

Frequently asked questions

What is CVE-2026-53947?: Ghost is a Node.js content management system. From 5.18.0 until 6.21.1, a discrepancy in responses from the members signin endpoints made it possible for an unauthenticated attacker to determine whether a given email address belongs to a registered member of a Ghost site. This vulnerability is fixed in 6.21.1.
How severe is CVE-2026-53947?: CVE-2026-53947 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2026-53947 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (11th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-53947?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-53947 have an EU (EUVD) identifier?: Yes. CVE-2026-53947 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-39022.
When was CVE-2026-53947 published?: CVE-2026-53947 was published on 2026-06-24 and last updated on 2026-06-25.

References

https://github.com/TryGhost/Ghost/security/advisories/GHSA-chgm-3698-jm42

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