CVE-2026-9545 (GCVE-0-2026-9545)
Vulnerability from cvelistv5
Published
2026-07-03 06:17
Modified
2026-07-06 16:53
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CWE
Summary
In this scenario, libcurl first uses a proper HTTP/3 server for the initial transfers, and when it makes a second transfer to the same site it has been replaced by the attacker's impostor machine - without a valid certificate. When libcurl returns to the hostname the second time with a cached SSL session (`CURLOPT_SSL_SESSIONID_CACHE` is not disabled) and early data enabled (the `CURLSSLOPT_EARLYDATA` bit is set in `CURLOPT_SSL_OPTIONS`), libcurl might send off the second request's bytes on that new connection *before* enforcing the certificate verification failure. Potentially leaking sensitive information.
References
Impacted products
Vendor Product Version
curl curl Version: 8.20.0   ≤ 8.20.0
Version: 8.19.0   ≤ 8.19.0
Version: 8.18.0   ≤ 8.18.0
Version: 8.17.0   ≤ 8.17.0
Version: 8.16.0   ≤ 8.16.0
Version: 8.15.0   ≤ 8.15.0
Version: 8.14.1   ≤ 8.14.1
Version: 8.14.0   ≤ 8.14.0
Version: 8.13.0   ≤ 8.13.0
Version: 8.12.1   ≤ 8.12.1
Version: 8.12.0   ≤ 8.12.0
Version: 8.11.1   ≤ 8.11.1
Version: 8.11.0   ≤ 8.11.0
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