CVE-2021-22901
curl 7.75.0 through 7.76.1 suffers from a use-after-free vulnerability resulting in already freed memory being used when a TLS 1.3 session ticket arrives over a connection. A malicious server can use this in rare unfortunate circumstances to potentially reach remote code execution in the client. When libcurl at run-time sets up support for TLS 1.3 session tickets on a connection using OpenSSL, it stores pointers to the transfer in-memory object for later retrieval when a session ticket arrives. If the connection is used by multiple transfers (like with a reused HTTP/1.1 connection or multiplexed HTTP/2 connection) that first transfer object might be freed before the new session is established on that connection and then the function will access a memory buffer that might be freed. When using that memory, libcurl might even call a function pointer in the object, making it possible for a remote code execution if the server could somehow manage to get crafted memory content into the correct place in memory.
- CVSS 3.1
- 8.1
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS
- 64% chance of exploitation in the next 30 days; higher than 99% of CVEs (scores of 2026-10-25)
- CWE
- CWE-416
- Published
- Modified
- Record from
- the NVD, synced
Affected
- haxx:curl
- netapp:active_iq_unified_manager
- netapp:cloud_backup
- netapp:h300e_firmware
- netapp:h300s_firmware
- netapp:h410s_firmware
- netapp:h500e_firmware
- netapp:h500s_firmware
- netapp:h700e_firmware
- netapp:h700s_firmware
- netapp:hci_compute_node_firmware
- netapp:oncommand_insight
- netapp:oncommand_workflow_automation
- netapp:snapcenter
- netapp:solidfire\,_enterprise_sds_\&_hci_storage_node
- netapp:solidfire_\&_hci_management_node
- netapp:solidfire_baseboard_management_controller_firmware
- oracle:communications_cloud_native_core_binding_support_function
- oracle:communications_cloud_native_core_network_function_cloud_native_environment
- oracle:communications_cloud_native_core_network_repository_function
- oracle:communications_cloud_native_core_network_slice_selection_function
- oracle:communications_cloud_native_core_service_communication_proxy
- oracle:essbase
- oracle:mysql_server
- siemens:sinec_infrastructure_network_services
- splunk:universal_forwarder