{"id":"CVE-2021-22897","aliases":["ALPINE-CVE-2021-22897","AZL-6358","BELL-CVE-2021-22897","CURL-CVE-2021-22897","EUVD-2021-10029","GHSA-frcg-47mh-pj2g","JLSEC-2026-1333","OESA-2021-1216"],"status":"published","title":"curl 7.61.0 through 7.76.1 suffers from exposure of data element to wrong session due to a...","description":"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 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.","severity":{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-12","score":0.04265,"percentile":0.91209,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-668","CWE-840"],"published":"2021-05-26T08:00:00Z","modified":"2026-10-25T01:04:45Z","fixes":[{"ecosystem":"Azure Linux:2","package":"curl","fixed_in":["7.76.0-5"],"sources":["osv"]},{"ecosystem":"Julia","package":"LibCURL_jll","fixed_in":["7.81.0+0"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Azure Linux:2","package":"curl","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"7.76.0-5"}]}]},{"source":"osv","ecosystem":"Julia","package":"LibCURL_jll","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"7.81.0+0"}]}]},{"source":"osv","ecosystem":"openEuler:20.03-LTS-SP1","package":"curl","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"7.71.1-7.oe1"}]}],"bundled":2}],"products":[{"vendor":"haxx","product":"curl"},{"vendor":"netapp","product":"cloud_backup"},{"vendor":"netapp","product":"h300e_firmware"},{"vendor":"netapp","product":"h300s_firmware"},{"vendor":"netapp","product":"h410s_firmware"},{"vendor":"netapp","product":"h500e_firmware"},{"vendor":"netapp","product":"h500s_firmware"},{"vendor":"netapp","product":"h700e_firmware"},{"vendor":"netapp","product":"h700s_firmware"},{"vendor":"netapp","product":"hci_compute_node_firmware"},{"vendor":"netapp","product":"solidfire\\,_enterprise_sds_\\\u0026_hci_storage_node"},{"vendor":"netapp","product":"solidfire_\\\u0026_hci_management_node"},{"vendor":"netapp","product":"solidfire_baseboard_management_controller_firmware"},{"vendor":"oracle","product":"communications_cloud_native_core_binding_support_function"},{"vendor":"oracle","product":"communications_cloud_native_core_network_function_cloud_native_environment"},{"vendor":"oracle","product":"communications_cloud_native_core_network_repository_function"},{"vendor":"oracle","product":"communications_cloud_native_core_network_slice_selection_function"},{"vendor":"oracle","product":"communications_cloud_native_core_service_communication_proxy"},{"vendor":"oracle","product":"essbase"},{"vendor":"oracle","product":"mysql_server"},{"vendor":"siemens","product":"simatic s7-1500 cpu 1518-4 pn/dp mfp"},{"vendor":"siemens","product":"simatic s7-1500 cpu 1518f-4 pn/dp mfp"},{"vendor":"siemens","product":"sinec_infrastructure_network_services"},{"vendor":"siemens","product":"siplus s7-1500 cpu 1518-4 pn/dp mfp"},{"vendor":"splunk","product":"universal_forwarder"}],"references":[{"url":"https://hackerone.com/reports/1172857","tags":["x_refsource_MISC","x_transferred","exploit","Exploit","Issue Tracking","Third Party Advisory","report","web"]},{"url":"https://curl.se/docs/CVE-2021-22897.html","tags":["x_refsource_MISC","x_transferred","Patch","Vendor Advisory","fix","web"]},{"url":"https://github.com/curl/curl/commit/bbb71507b7bab52002f9b1e0880bed6a32834511","tags":["x_refsource_MISC","x_transferred","Patch","Third Party Advisory","fix","web"]},{"url":"https://www.oracle.com//security-alerts/cpujul2021.html","tags":["x_refsource_MISC","x_transferred","Patch","Third Party Advisory","fix","web"]},{"url":"https://www.oracle.com/security-alerts/cpujan2022.html","tags":["x_refsource_MISC","x_transferred","Patch","Third Party Advisory","fix","web"]},{"url":"https://security.netapp.com/advisory/ntap-20210727-0007/","tags":["x_refsource_CONFIRM","x_transferred","Third Party Advisory","advisory","web"]},{"url":"https://www.oracle.com/security-alerts/cpuapr2022.html","tags":["x_refsource_MISC","x_transferred","Patch","Third Party Advisory","fix","web"]},{"url":"https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf","tags":["x_refsource_CONFIRM","x_transferred","Patch","Third Party Advisory","fix","web"]},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-389290.html","tags":["web"]},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-398330.html","tags":["web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-22897","tags":["web","advisory"]},{"url":"https://security.netapp.com/advisory/ntap-20210727-0007"},{"url":"https://github.com/advisories/GHSA-frcg-47mh-pj2g"},{"url":"https://security.alpinelinux.org/vuln/CVE-2021-22897","tags":["advisory"]},{"url":"https://docs.bell-sw.com/security/cves/CVE-2021-22897","tags":["advisory"]},{"url":"https://openeuler.org/en/security/safety-bulletin/detail.html?id=openEuler-SA-2021-1216","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-22898","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2021-22897","description":"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 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.","status":"published","published":"2021-06-11T15:49:38Z","modified":"2026-10-14T10:21:15.069Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"adp"}],"cwes":["CWE-840"],"updated_at":"2026-11-02T14:32:57.701381Z"}],"euvd":[{"id":"EUVD-2021-10029","description":"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 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.","status":"published","published":"2021-06-11T15:49:38Z","modified":"2026-10-14T10:21:15Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T17:27:16.85534Z"}],"ghsa":[{"id":"GHSA-frcg-47mh-pj2g","title":"curl 7.61.0 through 7.76.1 suffers from exposure of data element to wrong session due to a...","description":"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 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.","status":"published","published":"2022-05-24T19:05:02Z","modified":"2026-10-14T12:32:27Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"cwes":["CWE-668"],"updated_at":"2026-11-02T15:13:24.812204Z"}],"nvd":[{"id":"CVE-2021-22897","description":"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 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.","status":"published","published":"2021-06-11T16:15:10.963Z","modified":"2026-10-14T11:16:52.62Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"primary"},{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"secondary"},{"version":"2.0","score":4.3,"vector":"AV:N/AC:M/Au:N/C:P/I:N/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-840","CWE-668"],"updated_at":"2026-11-02T14:06:54.439974Z"}],"osv":[{"id":"ALPINE-CVE-2021-22897","description":"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 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.","status":"withdrawn","published":"2021-06-11T16:15:10.963Z","modified":"2026-07-14T08:03:28.331234385Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T15:27:48.646074Z"},{"id":"AZL-6358","title":"CVE-2021-22897 affecting package curl for versions less than 7.76.0-5","description":"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 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.","status":"published","published":"2021-06-11T16:15:10Z","modified":"2026-04-21T04:32:10.41781Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T15:28:07.805289Z"},{"id":"BELL-CVE-2021-22897","title":"CVE-2021-22897 does not affect BellSoft software","status":"withdrawn","published":"2023-08-31T12:15:35.321054Z","modified":"2026-01-26T09:47:42.996624Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T15:28:15.925958Z"},{"id":"CVE-2021-22897","description":"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 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.","status":"published","published":"2021-06-11T16:15:10.963Z","modified":"2026-10-24T14:51:04.912090449Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T15:44:18.367807Z"},{"id":"JLSEC-2026-1333","description":"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 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.","status":"published","published":"2026-08-17T13:15:13.4Z","modified":"2026-08-17T13:30:03.105379144Z","cvss":[{"version":"2.0","score":4.3,"vector":"AV:N/AC:M/Au:N/C:P/I:N/A:N","level":"medium"},{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T15:47:18.159338Z"},{"id":"OESA-2021-1216","title":"curl security update","description":"cURL is a computer software project providing a library (libcurl) and command-line tool (curl) for transferring data using various protocols.\r\n\r\nSecurity Fix(es):\r\n\r\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.(CVE-2021-22897)\r\n\r\ncurl 7.7 through 7.76.1 suffers from an information disclosure when the `-t` command line option, known as `CURLOPT_TELNETOPTIONS` in libcurl, is used to send variable=content pairs to TELNET servers. Due to a flaw in the option parser for sending NEW_ENV variables, libcurl could be made to pass on uninitialized data from a stack based buffer to the server, resulting in potentially revealing sensitive internal information to the server using a clear-text network protocol.(CVE-2021-22898)","status":"published","published":"2021-06-12T11:04:27Z","modified":"2026-08-18T01:15:31.084693968Z","cvss":[{"version":"3.1","score":5.9,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T15:52:38.987987Z"},{"id":"CURL-CVE-2021-22897","title":"Schannel cipher selection surprise","description":"libcurl lets applications specify which specific TLS ciphers to use in\ntransfers, using the option called `CURLOPT_SSL_CIPHER_LIST`. The cipher\nselection is used for the TLS negotiation when a transfer is done involving\nany of the TLS based transfer protocols libcurl supports, such as HTTPS, FTPS,\nIMAPS, POP3S, SMTPS etc.\n\nDue to a mistake in the code, the selected cipher set was stored in a single\n\"static\" variable in the library, which has the surprising side-effect that if\nan application sets up multiple concurrent transfers, the last one that sets\nthe ciphers accidentally controls the set used by all transfers. In a\nworst-case scenario, this weakens transport security significantly.","status":"published","published":"2021-05-26T08:00:00Z","modified":"2026-10-25T01:04:45.728326687Z","updated_at":"2026-11-02T15:43:55.669514Z"}]}}