Description
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
References3
- curl.se/docs/CVE-2026-80229.html PatchVendor Advisory
- curl.se/docs/CVE-2026-80229.json Vendor Advisory
- hackerone.com/reports/3969255 ExploitMitigationThird Party Advisory
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 1% percentile: 47 · as of 3 November 2026
- CWE
- CWE-416
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