Medium severity · published May 28, 2025
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
6.5
CVSS
0.3%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 23% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CU
Curl · Haxx
8.8.0 before 8.14.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-4947
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-4947
Patch
https://curl.se/docs/CVE-2025-4947.html
Vendor Advisory
https://curl.se/docs/CVE-2025-4947.json
Exploit
https://hackerone.com/reports/3150884
Mailing List
http://www.openwall.com/lists/oss-security/2025/05/28/4
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