CVE-2021-40438Critical· 9.0▾ Hadal⚠ Exploited in the wildPoC availableA crafted request uri-path can cause mod_proxy to forward the request to an origin server choosen by the remote user. This issue affects Apache HTTP Server 2.4.48 and earlier.
▾ Hadal zone — Critical and actively exploited (CISA KEV / 0day)
impact 49.5 · likelihood 20 · exploitation 25 · ransomware 5
A public proof-of-concept already exists for this vulnerability — see Exploit availability below.
Public exploit / PoC code seen in 2 sources. Availability, not in-the-wild use.
Exploit-prediction probability, daily snapshots since Aug 1.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
Federal remediation due Dec 15, 2021
Last analysed / modified upstream
100%
11 GitHub repos · Nuclei ×1
Added to the CISA catalog on Dec 1, 2021. Federal remediation due Dec 15, 2021. View catalog ↗
A crafted request uri-path can cause mod_proxy to forward the request to an origin server choosen by the remote user. This issue affects Apache HTTP Server 2.4.48 and earlier.
rocky_linux = 8.0enterprise_linux = 8.0enterprise_linux_eus = 8.1enterprise_linux_eus = 8.2enterprise_linux_eus = 8.4enterprise_linux_eus = 8.6enterprise_linux_eus = 8.8enterprise_linux_for_arm_64 = 8.0enterprise_linux_for_arm_64_eus = 8.6enterprise_linux_for_arm_64_eus = 8.8enterprise_linux_for_ibm_z_systems = 7.0_s390xenterprise_linux_for_ibm_z_systems = 8.0enterprise_linux_for_ibm_z_systems_eus = 8.1enterprise_linux_for_ibm_z_systems_eus = 8.4enterprise_linux_for_ibm_z_systems_eus = 8.8enterprise_linux_for_ibm_z_systems_eus_s390x = 8.2enterprise_linux_for_power_big_endian = 7.0enterprise_linux_for_power_little_endian = 7.0enterprise_linux_for_power_little_endian = 8.0enterprise_linux_for_power_little_endian_eus = 8.1enterprise_linux_for_power_little_endian_eus = 8.2enterprise_linux_for_power_little_endian_eus = 8.4enterprise_linux_for_power_little_endian_eus = 8.6enterprise_linux_for_power_little_endian_eus = 8.8enterprise_linux_for_scientific_computing = 7.0enterprise_linux_server = 7.0enterprise_linux_server_aus = 7.2enterprise_linux_server_aus = 7.3enterprise_linux_server_aus = 7.4enterprise_linux_server_aus = 7.6enterprise_linux_server_aus = 7.7enterprise_linux_server_aus = 8.2enterprise_linux_server_aus = 8.4enterprise_linux_server_aus = 8.6enterprise_linux_server_for_power_little_endian_update_services_for_sap_solutions = 7.6enterprise_linux_server_for_power_little_endian_update_services_for_sap_solutions = 7.7enterprise_linux_server_for_power_little_endian_update_services_for_sap_solutions = 8.1enterprise_linux_server_for_power_little_endian_update_services_for_sap_solutions = 8.2enterprise_linux_server_for_power_little_endian_update_services_for_sap_solutions = 8.4enterprise_linux_server_for_power_little_endian_update_services_for_sap_solutions = 8.6enterprise_linux_server_for_power_little_endian_update_services_for_sap_solutions = 8.8enterprise_linux_server_tus = 7.6enterprise_linux_server_tus = 7.7enterprise_linux_server_tus = 8.2enterprise_linux_server_tus = 8.4enterprise_linux_server_tus = 8.6enterprise_linux_server_tus = 8.8enterprise_linux_server_update_services_for_sap_solutions = 7.6enterprise_linux_server_update_services_for_sap_solutions = 7.7enterprise_linux_update_services_for_sap_solutions = 8.1enterprise_linux_update_services_for_sap_solutions = 8.2enterprise_linux_update_services_for_sap_solutions = 8.4enterprise_linux_update_services_for_sap_solutions = 8.6enterprise_linux_update_services_for_sap_solutions = 8.8enterprise_linux_workstation = 7.0jboss_core_services = 1.0software_collections = 1.0http_server <= 2.4.48fedora = 34fedora = 35debian_linux = 9.0debian_linux = 10.0debian_linux = 11.0cloud_backupclustered_data_ontapstoragegridbrocade_fabric_operating_system_firmwaref5os >= 1.1.0, <= 1.1.4f5os >= 1.2.0, <= 1.2.1enterprise_manager_ops_center = 12.4.0.0http_server = 12.2.1.3.0http_server = 12.2.1.4.0instantis_enterprisetrack = 17.1instantis_enterprisetrack = 17.2instantis_enterprisetrack = 17.3secure_global_desktop = 5.6zfs_storage_appliance_kit = 8.8ruggedcom_nmssinec_nms < 1.0.3sinema_remote_connect_server < 3.1sinema_remote_connect_server = 3.2sinema_server = 14.0tenable.sc <= 5.19.1Upgrade past the affected range:
sinec_nms 1.0.3sinema_remote_connect_server 3.1Field changes observed since this record was first indexed.
Connected by shared product, vendor, weakness, or advisory.
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