Description
When doing TLS related transfers with reused easy or multi handles and altering the `CURLSSLOPT_NO_PARTIALCHAIN` option, libcurl could accidentally reuse a CA store cached in memory for which the partial chain option was reversed. Contrary to the user's wishes and expectations. This could make libcurl find and accept a trust chain that it otherwise would not.
Affected products
haxx: curl
References3
- curl.se/docs/CVE-2025-14819.html MitigationPatchVendor Advisory
- curl.se/docs/CVE-2025-14819.json Vendor Advisory
- www.openwall.com/lists/oss-security/2026/01/07/5 Mailing ListMitigationPatchThird Party Advisory
Metrics
- CVSS 3.1
-
5.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N - EPSS — exploit probability
- 1% percentile: 56 · as of 11 November 2026
- CWE
- CWE-295
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