CVE-2026-8932: Haxx Curl

High severity, CVSS 7.5. EPSS: 0.4% chance of exploitation in the next 30 days.

libcurl would reuse a previously created connection even when some mTLS config related option had been changed that should have prohibited reuse. libcurl keeps previously used connections in a connection pool for subsequent transfers to reuse if one of them matches the setup. However, some TLS settings related to client certificates were left out from the configuration match checks, making them match too easily. In particular options related to the private key.

Affected products

• Haxx Curl: from 7.7, before 8.21.0 (fixed in 8.21.0)

Published 2026-07-03. Last modified 2026-09-15.