CVE-2021-3449Medium· 5.9▾ TwilightPoC availableAn OpenSSL TLS server may crash if sent a maliciously crafted renegotiation ClientHello message from a client. If a TLSv1.2 renegotiation ClientHello omits the signature_algorithms extension (where it was present in the initial ClientHel…
▾ Twilight zone — High severity, or a signal on a lesser flaw
impact 32.5 · likelihood 12.7 · exploitation 12
A public proof-of-concept already exists for this vulnerability — see Exploit availability below.
Public exploit / PoC code seen in 1 source. Availability, not in-the-wild use.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
Last analysed / modified upstream
64%
1 GitHub repo (last check)
An OpenSSL TLS server may crash if sent a maliciously crafted renegotiation ClientHello message from a client. If a TLSv1.2 renegotiation ClientHello omits the signature_algorithms extension (where it was present in the initial ClientHello), but includes a signature_algorithms_cert extension then a NULL pointer dereference will result, leading to a crash and a denial of service attack. A server is only vulnerable if it has TLSv1.2 and renegotiation enabled (which is the default configuration). OpenSSL TLS clients are not impacted by this issue. All OpenSSL 1.1.1 versions are affected by this issue. Users of these versions should upgrade to OpenSSL 1.1.1k. OpenSSL 1.0.2 is not impacted by this issue. Fixed in OpenSSL 1.1.1k (Affected 1.1.1-1.1.1j).
openssl >= 1.1.1, < 1.1.1kdebian_linux = 9.0debian_linux = 10.0freebsd = 12.2active_iq_unified_managercloud_volumes_ontap_mediatore-series_performance_analyzeroncommand_insightoncommand_workflow_automationontap_select_deploy_administration_utilitysantricity_smi-s_providersnapcenterstoragegridlog_correlation_engine < 6.0.9nessus <= 8.13.1nessus_network_monitor = 5.11.0nessus_network_monitor = 5.11.1nessus_network_monitor = 5.12.0nessus_network_monitor = 5.12.1nessus_network_monitor = 5.13.0tenable.sc >= 5.13.0, <= 5.17.0fedora = 34web_gateway = 8.2.19web_gateway = 9.2.10web_gateway = 10.1.1web_gateway_cloud_service = 8.2.19web_gateway_cloud_service = 9.2.10web_gateway_cloud_service = 10.1.1quantum_security_management_firmware = r80.40quantum_security_management_firmware = r81multi-domain_management_firmware = r80.40multi-domain_management_firmware = r81quantum_security_gateway_firmware = r80.40quantum_security_gateway_firmware = r81communications_communications_policy_management = 12.6.0.0.0enterprise_manager_for_storage_management = 13.4.0.0essbase = 21.2graalvm = 19.3.5graalvm = 20.3.1.2graalvm = 21.0.0.2jd_edwards_enterpriseone_tools < 9.2.6.0jd_edwards_world_security = a9.4mysql_connectors <= 8.0.23mysql_server <= 5.7.33mysql_server >= 8.0.15, <= 8.0.23mysql_workbench <= 8.0.23peoplesoft_enterprise_peopletools = 8.57peoplesoft_enterprise_peopletools = 8.58peoplesoft_enterprise_peopletools = 8.59primavera_unifier >= 17.7, <= 17.12primavera_unifier = 19.12primavera_unifier = 20.12primavera_unifier = 21.12secure_backup < 18.1.0.1.0secure_global_desktop = 5.6zfs_storage_appliance_kit = 8.8sma100_firmware >= 10.2.0.0, < 10.2.1.0-17svcapture_client = 3.5sonicos = 7.0.1.0ruggedcom_rcm1224_firmware >= 6.2scalance_lpe9403_firmwarescalance_m-800_firmware >= 6.2scalance_s602_firmware >= 4.1scalance_s612_firmware >= 4.1scalance_s615_firmware >= 6.2scalance_s623_firmware >= 4.1scalance_s627-2m_firmware >= 4.1scalance_sc-600_firmware >= 2.0scalance_w700_firmware >= 6.5scalance_w1700_firmware >= 2.0scalance_xb-200_firmware < 4.3scalance_xc-200_firmware < 4.3scalance_xf-200ba_firmware < 4.3scalance_xm-400_firmware < 6.4scalance_xp-200_firmware < 4.3scalance_xr-300wg_firmware < 4.3scalance_xr524-8c_firmware < 6.4scalance_xr526-8c_firmware < 6.4scalance_xr528-6m_firmware < 6.4scalance_xr552-12_firmware < 6.4simatic_cloud_connect_7_firmware >= 1.1simatic_cloud_connect_7_firmwaresimatic_cp_1242-7_gprs_v2_firmware >= 3.1simatic_cp_1242-7_gprs_v2_firmwaresimatic_hmi_basic_panels_2nd_generation_firmwaresimatic_hmi_comfort_outdoor_panels_firmwaresimatic_hmi_ktp_mobile_panels_firmwaresimatic_mv500_firmwaresimatic_net_cp_1243-1_firmware >= 3.1simatic_net_cp1243-7_lte_eu_firmware >= 3.1simatic_net_cp1243-7_lte_us_firmware >= 3.1simatic_net_cp_1243-8_irc_firmware >= 3.1simatic_net_cp_1542sp-1_irc_firmware >= 2.1simatic_net_cp_1543-1_firmware >= 2.2, < 3.0simatic_net_cp_1543sp-1_firmware >= 2.1simatic_net_cp_1545-1_firmware >= 1.0simatic_pcs_7_telecontrol_firmwaresimatic_pcs_neo_firmwaresimatic_pdm_firmware >= 9.1.0.7simatic_process_historian_opc_ua_server_firmware >= 2019Upgrade past the affected range:
openssl 1.1.1klog_correlation_engine 6.0.9jd_edwards_enterpriseone_tools 9.2.6.0secure_backup 18.1.0.1.0sma100_firmware 10.2.1.0-17svscalance_xb-200_firmware 4.3scalance_xc-200_firmware 4.3scalance_xf-200ba_firmware 4.3scalance_xm-400_firmware 6.4scalance_xp-200_firmware 4.3scalance_xr-300wg_firmware 4.3scalance_xr524-8c_firmware 6.4scalance_xr526-8c_firmware 6.4scalance_xr528-6m_firmware 6.4scalance_xr552-12_firmware 6.4simatic_net_cp_1543-1_firmware 3.0Connected by shared product, vendor, weakness, or advisory.
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