{"id":"CVE-2021-22897","title":"curl 7.61.0 through 7.76.1 suffers from exposure of data element to wrong session due to a mistake in the code for CURLOPT_SSL_CIPHER_LIST when libcurl is built to use the Schannel TLS library","summary":"curl 7.61.0 through 7.76.1 suffers from exposure of data element to wrong session due to a mistake in the code for CURLOPT_SSL_CIPHER_LIST when libcurl is built to use the Schannel TLS library. The selected cipher set was stored in a sin…","severity":"medium","cvss":5.3,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","cwe":["CWE-840","CWE-668"],"vendor":"haxx","product":"curl","affected":["curl >= 7.61.0, <= 7.76.1","communications_cloud_native_core_binding_support_function = 1.11.0","communications_cloud_native_core_network_function_cloud_native_environment = 1.10.0","communications_cloud_native_core_network_repository_function = 1.15.0","communications_cloud_native_core_network_repository_function = 1.15.1","communications_cloud_native_core_network_slice_selection_function = 1.8.0","communications_cloud_native_core_service_communication_proxy = 1.15.0","essbase < 11.1.2.4.047","essbase >= 21.0, < 21.3","mysql_server <= 5.7.34","mysql_server >= 8.0.0, <= 8.0.25","cloud_backup","solidfire,_enterprise_sds_&_hci_storage_node","solidfire_&_hci_management_node","solidfire_baseboard_management_controller_firmware","hci_compute_node_firmware","h300e_firmware","h300s_firmware","h410s_firmware","h500e_firmware","h500s_firmware","h700e_firmware","h700s_firmware","sinec_infrastructure_network_services < 1.0.1.1","universal_forwarder >= 8.2.0, < 8.2.12","universal_forwarder >= 9.0.0, < 9.0.6","universal_forwarder = 9.1.0"],"patched":["essbase 21.3","sinec_infrastructure_network_services 1.0.1.1","universal_forwarder 9.0.6"],"published":"2021-06-11","updated":"2026-10-14","sourceUpdated":"2026-10-14T11:16:52.620","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2021-22897","references":[{"url":"https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf","label":"support@hackerone.com"},{"url":"https://curl.se/docs/CVE-2021-22897.html","label":"support@hackerone.com"},{"url":"https://github.com/curl/curl/commit/bbb71507b7bab52002f9b1e0880bed6a32834511","label":"support@hackerone.com"},{"url":"https://hackerone.com/reports/1172857","label":"support@hackerone.com"},{"url":"https://security.netapp.com/advisory/ntap-20210727-0007/","label":"support@hackerone.com"},{"url":"https://www.oracle.com//security-alerts/cpujul2021.html","label":"support@hackerone.com"},{"url":"https://www.oracle.com/security-alerts/cpuapr2022.html","label":"support@hackerone.com"},{"url":"https://www.oracle.com/security-alerts/cpujan2022.html","label":"support@hackerone.com"},{"url":"https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://curl.se/docs/CVE-2021-22897.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/curl/curl/commit/bbb71507b7bab52002f9b1e0880bed6a32834511","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://hackerone.com/reports/1172857","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.netapp.com/advisory/ntap-20210727-0007/","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.oracle.com//security-alerts/cpujul2021.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.oracle.com/security-alerts/cpuapr2022.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.oracle.com/security-alerts/cpujan2022.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-389290.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-398330.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"},{"url":"https://hackerone.com/reports/1172857","label":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"tags":["nvd"],"epss":0.02979,"epssPercentile":0.86949,"ingestedAt":"2026-10-14T11:27:22.124Z","slug":"CVE-2021-22897","body":"## Overview\n\ncurl 7.61.0 through 7.76.1 suffers from exposure of data element to wrong session due to a mistake in the code for CURLOPT_SSL_CIPHER_LIST when libcurl is built to use the Schannel TLS library. The selected cipher set was stored in a single \"static\" variable in the library, which has the surprising side-effect that if an application sets up multiple concurrent transfers, the last one that sets the ciphers will accidentally control the set used by all transfers. In a worst-case scenario, this weakens transport security significantly.\n\n## Affected\n\n- `curl >= 7.61.0, <= 7.76.1`\n- `communications_cloud_native_core_binding_support_function = 1.11.0`\n- `communications_cloud_native_core_network_function_cloud_native_environment = 1.10.0`\n- `communications_cloud_native_core_network_repository_function = 1.15.0`\n- `communications_cloud_native_core_network_repository_function = 1.15.1`\n- `communications_cloud_native_core_network_slice_selection_function = 1.8.0`\n- `communications_cloud_native_core_service_communication_proxy = 1.15.0`\n- `essbase < 11.1.2.4.047`\n- `essbase >= 21.0, < 21.3`\n- `mysql_server <= 5.7.34`\n- `mysql_server >= 8.0.0, <= 8.0.25`\n- `cloud_backup`\n- `solidfire,_enterprise_sds_&_hci_storage_node`\n- `solidfire_&_hci_management_node`\n- `solidfire_baseboard_management_controller_firmware`\n- `hci_compute_node_firmware`\n- `h300e_firmware`\n- `h300s_firmware`\n- `h410s_firmware`\n- `h500e_firmware`\n- `h500s_firmware`\n- `h700e_firmware`\n- `h700s_firmware`\n- `sinec_infrastructure_network_services < 1.0.1.1`\n- `universal_forwarder >= 8.2.0, < 8.2.12`\n- `universal_forwarder >= 9.0.0, < 9.0.6`\n- `universal_forwarder = 9.1.0`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `essbase 21.3`\n- `sinec_infrastructure_network_services 1.0.1.1`\n- `universal_forwarder 9.0.6`","depth":"sunlit","depthScore":30,"depthScoreParts":{"impact":29.2,"likelihood":0.6,"exploitation":0,"ransomware":0},"changes":[]}