What is CVE-2025-5025?

CVE-2025-5025 is a medium-severity vulnerability in Curl, classified under Improper Certificate Validation. CVSS score: 4.8/10. Published 2025-05-28.

How severe is CVE-2025-5025?

Medium severity. CVSS v3 base score is 4.8 out of 10.

Is CVE-2025-5025 known to be exploited?

5 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Vulnerability in Curl

CVE-2025-5025

libcurl supports *pinning* of the server certificate public key for HTTPS transfers. Due to an omission, this check is not performed when connecting with QUIC for HTTP/3, when the TLS backend is wolfSSL. Documentation says the option works with wolfSSL, failing to specify that it does not for QUIC and HTTP/3. Since pinning makes the transfer succeed if the pin is fine, users could unwittingly connect to an impostor server without noticing.

Vulnerability class: Improper Certificate Validation

EPSS: 0.003 (16.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.8 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N.

Affected products

Curl — versions 8.13.0, 8.12.1, 8.12.0
Haxx Curl

Weakness classification (CWE)

CWE-295 — Improper Certificate Validation

Public proof-of-concept exploits

References

2499f714-1537-4658-8207-48ae4bb9eae9 (Vendor Advisory)
2499f714-1537-4658-8207-48ae4bb9eae9 (Vendor Advisory)
2499f714-1537-4658-8207-48ae4bb9eae9 (Exploit, Third Party Advisory, Issue Tracking)
af854a3a-2127-422b-91ae-364da2661108 (Mailing List, Third Party Advisory)

Frequently asked questions

What is CVE-2025-5025?: CVE-2025-5025 is a medium-severity vulnerability in Curl, classified under Improper Certificate Validation. CVSS score: 4.8/10. Published 2025-05-28.
How severe is CVE-2025-5025?: Medium severity. CVSS v3 base score is 4.8 out of 10.
Is CVE-2025-5025 known to be exploited?: 5 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.