How severe is CVE-2025-4947?

CVE-2025-4947 has a CVSS 3.x base score of 6.5, 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 low, and availability none.

Is CVE-2025-4947 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (16th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-4947?

CVE-2025-4947 affects Haxx Curl. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-4947?

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

Does CVE-2025-4947 have an EU (EUVD) identifier?

Yes. CVE-2025-4947 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-16303.

When was CVE-2025-4947 published?

CVE-2025-4947 was published on 2025-05-28 and last updated on 2026-06-17.

CVE-2025-4947

CVE-2025-4947 is a medium-severity vulnerability in Haxx Curl with a CVSS 3.x base score of 6.5. 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-295.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 0% (16th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-16303
Weakness: CWE-295
Affected product: Haxx Curl
Published: 2025-05-28
Last modified: 2026-06-17

Description

libcurl accidentally skips the certificate verification for QUIC connections when connecting to a host specified as an IP address in the URL. Therefore, it does not detect impostors or man-in-the-middle attacks.

Frequently asked questions

What is CVE-2025-4947?: libcurl accidentally skips the certificate verification for QUIC connections when connecting to a host specified as an IP address in the URL. Therefore, it does not detect impostors or man-in-the-middle attacks.
How severe is CVE-2025-4947?: CVE-2025-4947 has a CVSS 3.x base score of 6.5, 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 low, and availability none.
Is CVE-2025-4947 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (16th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-4947?: CVE-2025-4947 affects Haxx Curl. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-4947?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-4947 have an EU (EUVD) identifier?: Yes. CVE-2025-4947 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-16303.
When was CVE-2025-4947 published?: CVE-2025-4947 was published on 2025-05-28 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:haxx:curl:*:*:*:*:*:*:*:*

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