How severe is CVE-2025-13034?

CVE-2025-13034 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2025-13034 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (13th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-13034?

CVE-2025-13034 affects Haxx Curl. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-13034?

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

Does CVE-2025-13034 have an EU (EUVD) identifier?

Yes. CVE-2025-13034 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-1572.

When was CVE-2025-13034 published?

CVE-2025-13034 was published on 2026-01-08 and last updated on 2026-06-17.

CVE-2025-13034

CVE-2025-13034 is a medium-severity vulnerability in Haxx Curl with a CVSS 3.x base score of 5.9. 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 5.9)
EPSS exploit prediction: 0% (13th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-1572
Weakness: CWE-295
Affected product: Haxx Curl
Published: 2026-01-08
Last modified: 2026-06-17

Description

When using `CURLOPT_PINNEDPUBLICKEY` option with libcurl or `--pinnedpubkey` with the curl tool,curl should check the public key of the server certificate to verify the peer. This check was skipped in a certain condition that would then make curl allow the connection without performing the proper check, thus not noticing a possible impostor. To skip this check, the connection had to be done with QUIC with ngtcp2 built to use GnuTLS and the user had to explicitly disable the standard certificate verification.

Frequently asked questions

What is CVE-2025-13034?: When using `CURLOPT_PINNEDPUBLICKEY` option with libcurl or `--pinnedpubkey` with the curl tool,curl should check the public key of the server certificate to verify the peer. This check was skipped in a certain condition that would then make curl allow the connection without performing the proper check, thus not noticing a possible impostor. To skip this check, the connection had to be done with QUIC with ngtcp2 built to use GnuTLS and the user had to explicitly disable the standard certificate verification.
How severe is CVE-2025-13034?: CVE-2025-13034 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2025-13034 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (13th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-13034?: CVE-2025-13034 affects Haxx Curl. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-13034?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-13034 have an EU (EUVD) identifier?: Yes. CVE-2025-13034 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-1572.
When was CVE-2025-13034 published?: CVE-2025-13034 was published on 2026-01-08 and last updated on 2026-06-17.

References

Affected products (1)

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

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