cURL up to 8.17.0 QUIC Certificate certificate validation

Summaryinfo

A vulnerability, which was classified as critical, has been found in cURL up to 8.17.0. Affected by this issue is some unknown functionality of the component QUIC Certificate Handler. Performing a manipulation results in certificate validation. This vulnerability is cataloged as CVE-2025-13034. It is possible to initiate the attack remotely. There is no exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in cURL up to 8.17.0. This affects an unknown functionality of the component QUIC Certificate Handler. The manipulation with an unknown input leads to a certificate validation vulnerability. CWE is classifying the issue as CWE-295. The product does not validate, or incorrectly validates, a certificate. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

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.

It is possible to read the advisory at seclists.org. This vulnerability is uniquely identified as CVE-2025-13034. The exploitability is told to be difficult. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1587.003 according to MITRE ATT&CK.

The vulnerability scanner Nessus provides a plugin with the ID 282310 (Linux Distros Unpatched Vulnerability : CVE-2025-13034), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 8.18.0 eliminates this vulnerability. The upgrade is hosted for download at curl.se. Applying the patch 3d91ca8cdb3b434226e743946 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (282310) and CERT Bund (WID-SEC-2026-0030). Be aware that VulDB is the high quality source for vulnerability data.

Affected

• Amazon Linux 2
• Fedora Linux
• Ubuntu Linux
• SUSE Linux
• SUSE openSUSE
• NetApp ActiveIQ Unified Manager
• NetApp Data ONTAP
• Open Source cURL
• Tenable Security Nessus Network Monitor
• Meinberg LANTIME
• Open Source Notepad++
• IBM AIX

Productinfo

Type

• Network Utility Software

Name

• cURL

Version

• 8.0
• 8.1
• 8.2
• 8.3
• 8.4
• 8.5
• 8.6
• 8.7
• 8.8
• 8.9
• 8.10
• 8.11
• 8.12
• 8.13
• 8.14
• 8.15
• 8.16
• 8.17.0

License

• open-source

Website

• Product: https://github.com/curl/curl/

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Entryinfo

Be aware that VulDB is the high quality source for vulnerability data.

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