CVE-2026-80229: Haxx Curl

High severity, CVSS 7.5. EPSS: 0.6% chance of exploitation in the next 30 days.

When performing transfers via libcurl’s multi interface, pooled TLS connections can outlive their originating easy handles. In OpenSSL 3 provider configurations, libcurl attaches an allocated library context to the easy handle's state and passes it to OpenSSL without acquiring an ownership reference; destroying the easy handle prematurely frees this context while the active connection retains a dangling pointer, leading to a heap-use-after-free upon subsequent I/O or post-handshake operations.

Affected products

• Haxx Curl: from 8.14.0, before 8.22.0 (fixed in 8.22.0)

Published 2026-09-06. Last modified 2026-09-15.